3121808231 has 4 divisors (see below), whose sum is σ = 3121956912. Its totient is φ = 3121659552.

The previous prime is 3121808227. The next prime is 3121808237. The reversal of 3121808231 is 1328081213.

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

It is a cyclic number.

It is not a de Polignac number, because 3121808231 - 2² = 3121808227 is a prime.

It is a super-2 number, since 2×3121808231² = 19491373262278698722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3121808194 and 3121808203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121808237) 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, 36386 + ... + 86991.

It is an arithmetic number, because the mean of its divisors is an integer number (780489228).

Almost surely, 2^3121808231 is an apocalyptic number.

3121808231 is a deficient number, since it is larger than the sum of its proper divisors (148681).

3121808231 is a wasteful number, since it uses less digits than its factorization.

3121808231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148680.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 3121808231 is about 55873.1440944574. The cubic root of 3121808231 is about 1461.5109507931.

Adding to 3121808231 its reverse (1328081213), we get a palindrome (4449889444).

The spelling of 3121808231 in words is "three billion, one hundred twenty-one million, eight hundred eight thousand, two hundred thirty-one".