21974642 has 16 divisors (see below), whose sum is σ = 35396352. Its totient is φ = 10194240.

The previous prime is 21974627. The next prime is 21974651. The reversal of 21974642 is 24647912.

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, 2138 + ... + 6965.

It is an arithmetic number, because the mean of its divisors is an integer number (2212272).

Almost surely, 2^21974642 is an apocalyptic number.

21974642 is a deficient number, since it is larger than the sum of its proper divisors (13421710).

21974642 is a wasteful number, since it uses less digits than its factorization.

21974642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9193.

The product of its digits is 24192, while the sum is 35.

The square root of 21974642 is about 4687.7118085480. The cubic root of 21974642 is about 280.0962339281.

The spelling of 21974642 in words is "twenty-one million, nine hundred seventy-four thousand, six hundred forty-two".