21173072 has 20 divisors (see below), whose sum is σ = 41637216. Its totient is φ = 10428000.

The previous prime is 21173057. The next prime is 21173081. The reversal of 21173072 is 27037112.

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, 8804 + ... + 10947.

Almost surely, 2^21173072 is an apocalyptic number.

It is an amenable number.

21173072 is a deficient number, since it is larger than the sum of its proper divisors (20464144).

21173072 is a wasteful number, since it uses less digits than its factorization.

21173072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19826 (or 19820 counting only the distinct ones).

The product of its (nonzero) digits is 588, while the sum is 23.

The square root of 21173072 is about 4601.4206501905. The cubic root of 21173072 is about 276.6482696110.

The spelling of 21173072 in words is "twenty-one million, one hundred seventy-three thousand, seventy-two".