21973910 has 32 divisors (see below), whose sum is σ = 46172160. Its totient is φ = 7372512.

The previous prime is 21973907. The next prime is 21973933. The reversal of 21973910 is 1937912.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50 + ... + 6629.

It is an arithmetic number, because the mean of its divisors is an integer number (1442880).

Almost surely, 2^21973910 is an apocalyptic number.

21973910 is an abundant number, since it is smaller than the sum of its proper divisors (24198250).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21973910 is a wasteful number, since it uses less digits than its factorization.

21973910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6740.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 21973910 is about 4687.6337314257. The cubic root of 21973910 is about 280.0931237869.

The spelling of 21973910 in words is "twenty-one million, nine hundred seventy-three thousand, nine hundred ten".