21927638 has 8 divisors (see below), whose sum is σ = 32918088. Its totient is φ = 10954944.

The previous prime is 21927629. The next prime is 21927641. The reversal of 21927638 is 83672912.

It is a sphenic number, since it is the product of 3 distinct primes.

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, 731 + ... + 6662.

It is an arithmetic number, because the mean of its divisors is an integer number (4114761).

Almost surely, 2^21927638 is an apocalyptic number.

21927638 is a deficient number, since it is larger than the sum of its proper divisors (10990450).

21927638 is a wasteful number, since it uses less digits than its factorization.

21927638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8878.

The product of its digits is 36288, while the sum is 38.

The square root of 21927638 is about 4682.6955912167. The cubic root of 21927638 is about 279.8963817272.

The spelling of 21927638 in words is "twenty-one million, nine hundred twenty-seven thousand, six hundred thirty-eight".