21750966 has 12 divisors (see below), whose sum is σ = 47127132. Its totient is φ = 7250316.

The previous prime is 21750959. The next prime is 21750983. The reversal of 21750966 is 66905712.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21750966.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 604176 + ... + 604211.

It is an arithmetic number, because the mean of its divisors is an integer number (3927261).

Almost surely, 2^21750966 is an apocalyptic number.

21750966 is an abundant number, since it is smaller than the sum of its proper divisors (25376166).

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

21750966 is a wasteful number, since it uses less digits than its factorization.

21750966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1208395 (or 1208392 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 21750966 is about 4663.7930914654. The cubic root of 21750966 is about 279.1426410551.

The spelling of 21750966 in words is "twenty-one million, seven hundred fifty thousand, nine hundred sixty-six".