21929815368 has 64 divisors (see below), whose sum is σ = 60981048000. Its totient is φ = 7302151296.

The previous prime is 21929815367. The next prime is 21929815379. The reversal of 21929815368 is 86351892912.

21929815368 is a `hidden beast` number, since 2 + 1 + 9 + 29 + 81 + 536 + 8 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (21929815367) 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 15 ways as a sum of consecutive naturals, for example, 150948 + ... + 258156.

It is an arithmetic number, because the mean of its divisors is an integer number (952828875).

Almost surely, 2^21929815368 is an apocalyptic number.

It is an amenable number.

21929815368 is an abundant number, since it is smaller than the sum of its proper divisors (39051232632).

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

21929815368 is a wasteful number, since it uses less digits than its factorization.

21929815368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108171 (or 108161 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 54.

The spelling of 21929815368 in words is "twenty-one billion, nine hundred twenty-nine million, eight hundred fifteen thousand, three hundred sixty-eight".