21121011982 has 64 divisors (see below), whose sum is σ = 38144701440. Its totient is φ = 8580096000.

The previous prime is 21121011959. The next prime is 21121012021. The reversal of 21121011982 is 28911012112.

It is a self number, because there is not a number n which added to its sum of digits gives 21121011982.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7406857 + ... + 7409707.

It is an arithmetic number, because the mean of its divisors is an integer number (596010960).

Almost surely, 2^21121011982 is an apocalyptic number.

21121011982 is a deficient number, since it is larger than the sum of its proper divisors (17023689458).

21121011982 is a wasteful number, since it uses less digits than its factorization.

21121011982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217.

The product of its (nonzero) digits is 576, while the sum is 28.

The spelling of 21121011982 in words is "twenty-one billion, one hundred twenty-one million, eleven thousand, nine hundred eighty-two".