21173012 has 12 divisors (see below), whose sum is σ = 42346080. Its totient is φ = 9074136.

The previous prime is 21172999. The next prime is 21173021. The reversal of 21173012 is 21037112.

21173012 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 378062 + ... + 378117.

It is an arithmetic number, because the mean of its divisors is an integer number (3528840).

Almost surely, 2^21173012 is an apocalyptic number.

It is an amenable number.

21173012 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21173012 is a wasteful number, since it uses less digits than its factorization.

21173012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 756190 (or 756188 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 21173012 is about 4601.4141304603. The cubic root of 21173012 is about 276.6480082899.

The spelling of 21173012 in words is "twenty-one million, one hundred seventy-three thousand, twelve".