3157297921 has 8 divisors (see below), whose sum is σ = 3191702184. Its totient is φ = 3123079680.

The previous prime is 3157297909. The next prime is 3157297939. The reversal of 3157297921 is 1297927513.

It can be written as a sum of positive squares in 4 ways, for example, as 2927351025 + 229946896 = 54105^2 + 15164^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3157297921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3157237921) 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, 12240 + ... + 80401.

It is an arithmetic number, because the mean of its divisors is an integer number (398962773).

Almost surely, 2^3157297921 is an apocalyptic number.

It is an amenable number.

3157297921 is a deficient number, since it is larger than the sum of its proper divisors (34404263).

3157297921 is a wasteful number, since it uses less digits than its factorization.

3157297921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93011.

The product of its digits is 238140, while the sum is 46.

The square root of 3157297921 is about 56189.8382361081. The cubic root of 3157297921 is about 1467.0283994529.

The spelling of 3157297921 in words is "three billion, one hundred fifty-seven million, two hundred ninety-seven thousand, nine hundred twenty-one".