3121213644 has 36 divisors (see below), whose sum is σ = 7912503144. Its totient is φ = 1037402112.

The previous prime is 3121213637. The next prime is 3121213673. The reversal of 3121213644 is 4463121213.

It is a happy number.

3121213644 is a `hidden beast` number, since 3 + 1 + 2 + 1 + 2 + 13 + 644 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×3121213644² = 19483949222983517472, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112437 + ... + 137420.

It is an arithmetic number, because the mean of its divisors is an integer number (219791754).

Almost surely, 2^3121213644 is an apocalyptic number.

It is an amenable number.

3121213644 is an abundant number, since it is smaller than the sum of its proper divisors (4791289500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3121213644 is a wasteful number, since it uses less digits than its factorization.

3121213644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250214 (or 250209 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 3121213644 is about 55867.8229753048. The cubic root of 3121213644 is about 1461.4181572876.

Adding to 3121213644 its reverse (4463121213), we get a palindrome (7584334857).

The spelling of 3121213644 in words is "three billion, one hundred twenty-one million, two hundred thirteen thousand, six hundred forty-four".