21620974 has 16 divisors (see below), whose sum is σ = 36147600. Its totient is φ = 9638784.

The previous prime is 21620953. The next prime is 21620999. The reversal of 21620974 is 47902612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16089 + ... + 17380.

It is an arithmetic number, because the mean of its divisors is an integer number (2259225).

Almost surely, 2^21620974 is an apocalyptic number.

21620974 is a deficient number, since it is larger than the sum of its proper divisors (14526626).

21620974 is a wasteful number, since it uses less digits than its factorization.

21620974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33507.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 21620974 is about 4649.8359110833. The cubic root of 21620974 is about 278.5854422304.

The spelling of 21620974 in words is "twenty-one million, six hundred twenty thousand, nine hundred seventy-four".