21051566046 has 24 divisors (see below), whose sum is σ = 52127687664. Its totient is φ = 6014733120.

The previous prime is 21051566033. The next prime is 21051566051. The reversal of 21051566046 is 64066515012.

21051566046 is a `hidden beast` number, since 2 + 1 + 0 + 51 + 566 + 0 + 46 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21051566046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 83537835 + ... + 83538086.

It is an arithmetic number, because the mean of its divisors is an integer number (2171986986).

Almost surely, 2^21051566046 is an apocalyptic number.

21051566046 is an abundant number, since it is smaller than the sum of its proper divisors (31076121618).

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

21051566046 is a wasteful number, since it uses less digits than its factorization.

21051566046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167075936 (or 167075933 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 21051566046 in words is "twenty-one billion, fifty-one million, five hundred sixty-six thousand, forty-six".