21900979026 has 24 divisors (see below), whose sum is σ = 47814356304. Its totient is φ = 7244597880.

The previous prime is 21900979013. The next prime is 21900979031. The reversal of 21900979026 is 62097900912.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 4641616 + ... + 4646331.

It is an arithmetic number, because the mean of its divisors is an integer number (1992264846).

Almost surely, 2^21900979026 is an apocalyptic number.

21900979026 is an abundant number, since it is smaller than the sum of its proper divisors (25913377278).

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

21900979026 is a wasteful number, since it uses less digits than its factorization.

21900979026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9288086 (or 9288083 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The spelling of 21900979026 in words is "twenty-one billion, nine hundred million, nine hundred seventy-nine thousand, twenty-six".