15171345721 has 8 divisors (see below), whose sum is σ = 18092536704. Its totient is φ = 12438618720.

The previous prime is 15171345713. The next prime is 15171345809. The reversal of 15171345721 is 12754317151.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15171345721 - 2³ = 15171345713 is a prime.

It is a super-2 number, since 2×15171345721² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15171345221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47115820 + ... + 47116141.

It is an arithmetic number, because the mean of its divisors is an integer number (2261567088).

Almost surely, 2^15171345721 is an apocalyptic number.

It is an amenable number.

15171345721 is a deficient number, since it is larger than the sum of its proper divisors (2921190983).

15171345721 is an equidigital number, since it uses as much as digits as its factorization.

15171345721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94231991.

The product of its digits is 29400, while the sum is 37.

The spelling of 15171345721 in words is "fifteen billion, one hundred seventy-one million, three hundred forty-five thousand, seven hundred twenty-one".