21123576392 has 8 divisors (see below), whose sum is σ = 39606705750. Its totient is φ = 10561788192.

The previous prime is 21123576379. The next prime is 21123576433. The reversal of 21123576392 is 29367532112.

It can be written as a sum of positive squares in only one way, i.e., 17512287556 + 3611288836 = 132334^2 + 60094^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320223517 + ... + 1320223532.

Almost surely, 2^21123576392 is an apocalyptic number.

It is an amenable number.

21123576392 is a deficient number, since it is larger than the sum of its proper divisors (18483129358).

21123576392 is a wasteful number, since it uses less digits than its factorization.

21123576392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2640447055 (or 2640447051 counting only the distinct ones).

The product of its digits is 136080, while the sum is 41.

The spelling of 21123576392 in words is "twenty-one billion, one hundred twenty-three million, five hundred seventy-six thousand, three hundred ninety-two".