21031312158 has 48 divisors (see below), whose sum is σ = 45835695360. Its totient is φ = 6969331152.

The previous prime is 21031312157. The next prime is 21031312193. The reversal of 21031312158 is 85121313012.

It is a super-4 number, since 4×21031312158⁴ (a number of 42 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031312157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2762385 + ... + 2769987.

It is an arithmetic number, because the mean of its divisors is an integer number (954910320).

Almost surely, 2^21031312158 is an apocalyptic number.

21031312158 is an abundant number, since it is smaller than the sum of its proper divisors (24804383202).

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

21031312158 is a wasteful number, since it uses less digits than its factorization.

21031312158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8493 (or 8490 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The spelling of 21031312158 in words is "twenty-one billion, thirty-one million, three hundred twelve thousand, one hundred fifty-eight".