21255467166 has 24 divisors (see below), whose sum is σ = 48762543024. Its totient is φ = 6668381760.

The previous prime is 21255467153. The next prime is 21255467171. The reversal of 21255467166 is 66176455212.

21255467166 is a `hidden beast` number, since 2 + 1 + 25 + 5 + 467 + 166 = 666.

It is a super-3 number, since 3×21255467166³ (a number of 32 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34730850 + ... + 34731461.

It is an arithmetic number, because the mean of its divisors is an integer number (2031772626).

Almost surely, 2^21255467166 is an apocalyptic number.

21255467166 is an abundant number, since it is smaller than the sum of its proper divisors (27507075858).

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

21255467166 is a wasteful number, since it uses less digits than its factorization.

21255467166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69462336 (or 69462333 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The spelling of 21255467166 in words is "twenty-one billion, two hundred fifty-five million, four hundred sixty-seven thousand, one hundred sixty-six".