3157321 has 4 divisors (see below), whose sum is σ = 3242692. Its totient is φ = 3071952.

The previous prime is 3157313. The next prime is 3157337. The reversal of 3157321 is 1237513.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1990921 + 1166400 = 1411^2 + 1080^2 .

It is a cyclic number.

It is not a de Polignac number, because 3157321 - 2³ = 3157313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3157292 and 3157301.

It is not an unprimeable number, because it can be changed into a prime (3157391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42630 + ... + 42703.

It is an arithmetic number, because the mean of its divisors is an integer number (810673).

Almost surely, 2^3157321 is an apocalyptic number.

It is an amenable number.

3157321 is a deficient number, since it is larger than the sum of its proper divisors (85371).

3157321 is an equidigital number, since it uses as much as digits as its factorization.

3157321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85370.

The product of its digits is 630, while the sum is 22.

The square root of 3157321 is about 1776.8851960664. The cubic root of 3157321 is about 146.7031973972.

The spelling of 3157321 in words is "three million, one hundred fifty-seven thousand, three hundred twenty-one".