21915058516 has 96 divisors (see below), whose sum is σ = 42728878080. Its totient is φ = 9772963200.

The previous prime is 21915058507. The next prime is 21915058541. The reversal of 21915058516 is 61585051912.

It is a happy number.

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, 66208471 + ... + 66208801.

It is an arithmetic number, because the mean of its divisors is an integer number (445092480).

Almost surely, 2^21915058516 is an apocalyptic number.

21915058516 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21915058516 is a deficient number, since it is larger than the sum of its proper divisors (20813819564).

21915058516 is a wasteful number, since it uses less digits than its factorization.

21915058516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 725 (or 723 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 43.

The spelling of 21915058516 in words is "twenty-one billion, nine hundred fifteen million, fifty-eight thousand, five hundred sixteen".