21072190 has 16 divisors (see below), whose sum is σ = 38070000. Its totient is φ = 8397760.

The previous prime is 21072187. The next prime is 21072199. The reversal of 21072190 is 9127012.

It is a super-2 number, since 2×21072190² = 888074382792200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21072199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 940 + ... + 6559.

It is an arithmetic number, because the mean of its divisors is an integer number (2379375).

Almost surely, 2^21072190 is an apocalyptic number.

21072190 is a deficient number, since it is larger than the sum of its proper divisors (16997810).

21072190 is a wasteful number, since it uses less digits than its factorization.

21072190 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7787.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 21072190 is about 4590.4455121480. The cubic root of 21072190 is about 276.2081937514.

The spelling of 21072190 in words is "twenty-one million, seventy-two thousand, one hundred ninety".