21642165400250 has 32 divisors (see below), whose sum is σ = 41821041180672. Its totient is φ = 8377612410000.

The previous prime is 21642165400153. The next prime is 21642165400307. The reversal of 21642165400250 is 5200456124612.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1396260986 + ... + 1396276485.

It is an arithmetic number, because the mean of its divisors is an integer number (1306907536896).

Almost surely, 2^{21642165400250} is an apocalyptic number.

21642165400250 is a deficient number, since it is larger than the sum of its proper divisors (20178875780422).

21642165400250 is a wasteful number, since it uses less digits than its factorization.

21642165400250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2792537519 (or 2792537509 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 38.

The spelling of 21642165400250 in words is "twenty-one trillion, six hundred forty-two billion, one hundred sixty-five million, four hundred thousand, two hundred fifty".