21140972 has 6 divisors (see below), whose sum is σ = 36996708. Its totient is φ = 10570484.

The previous prime is 21140957. The next prime is 21141007. The reversal of 21140972 is 27904112.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2642618 + ... + 2642625.

It is an arithmetic number, because the mean of its divisors is an integer number (6166118).

Almost surely, 2^21140972 is an apocalyptic number.

It is an amenable number.

21140972 is a deficient number, since it is larger than the sum of its proper divisors (15855736).

21140972 is a wasteful number, since it uses less digits than its factorization.

21140972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5285247 (or 5285245 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 21140972 is about 4597.9312739535. The cubic root of 21140972 is about 276.5083922386.

The spelling of 21140972 in words is "twenty-one million, one hundred forty thousand, nine hundred seventy-two".