21945066264 has 120 divisors (see below), whose sum is σ = 67562598180. Its totient is φ = 6649996320.

The previous prime is 21945066259. The next prime is 21945066277. The reversal of 21945066264 is 46266054912.

21945066264 is a `hidden beast` number, since 2 + 19 + 4 + 5 + 0 + 6 + 626 + 4 = 666.

It is a congruent number.

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 in 29 ways as a sum of consecutive naturals, for example, 61534 + ... + 218349.

Almost surely, 2^21945066264 is an apocalyptic number.

21945066264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21945066264 is an abundant number, since it is smaller than the sum of its proper divisors (45617531916).

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

21945066264 is a wasteful number, since it uses less digits than its factorization.

21945066264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279923 (or 279899 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 21945066264 in words is "twenty-one billion, nine hundred forty-five million, sixty-six thousand, two hundred sixty-four".