3121213688 has 16 divisors (see below), whose sum is σ = 5860270680. Its totient is φ = 1558474848.

The previous prime is 3121213687. The next prime is 3121213721. The reversal of 3121213688 is 8863121213.

It is a happy number.

3121213688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×3121213688² = 19483949772317122688, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121213687) 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, 260270 + ... + 271997.

Almost surely, 2^3121213688 is an apocalyptic number.

It is an amenable number.

3121213688 is a deficient number, since it is larger than the sum of its proper divisors (2739056992).

3121213688 is a wasteful number, since it uses less digits than its factorization.

3121213688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533006 (or 533002 counting only the distinct ones).

The product of its digits is 13824, while the sum is 35.

The square root of 3121213688 is about 55867.8233690914. The cubic root of 3121213688 is about 1461.4181641549.

The spelling of 3121213688 in words is "three billion, one hundred twenty-one million, two hundred thirteen thousand, six hundred eighty-eight".