This number is a prime.
Smallest prime p with most distinct digits for which 10*p+1, 10*p+3, 10*p+7 and 10*p+9 are primes [Gupta]
Smallest prime p with most distinct digits for which
10*p+1, 10*p+3, 10*p+7 and 10*p+9 are primes [Gupta]