21118694924 has 12 divisors (see below), whose sum is σ = 39131699544. Its totient is φ = 9938209344.

The previous prime is 21118694903. The next prime is 21118694929. The reversal of 21118694924 is 42949681112.

It is not an unprimeable number, because it can be changed into a prime (21118694929) 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 3 ways as a sum of consecutive naturals, for example, 155284454 + ... + 155284589.

It is an arithmetic number, because the mean of its divisors is an integer number (3260974962).

Almost surely, 2^21118694924 is an apocalyptic number.

It is an amenable number.

21118694924 is a deficient number, since it is larger than the sum of its proper divisors (18013004620).

21118694924 is a wasteful number, since it uses less digits than its factorization.

21118694924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310569064 (or 310569062 counting only the distinct ones).

The product of its digits is 248832, while the sum is 47.

The spelling of 21118694924 in words is "twenty-one billion, one hundred eighteen million, six hundred ninety-four thousand, nine hundred twenty-four".