21590966 has 4 divisors (see below), whose sum is σ = 32386452. Its totient is φ = 10795482.

The previous prime is 21590957. The next prime is 21590983. The reversal of 21590966 is 66909512.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5397740 + ... + 5397743.

It is an arithmetic number, because the mean of its divisors is an integer number (8096613).

Almost surely, 2^21590966 is an apocalyptic number.

21590966 is a deficient number, since it is larger than the sum of its proper divisors (10795486).

21590966 is a wasteful number, since it uses less digits than its factorization.

21590966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10795485.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 21590966 is about 4646.6080101511. The cubic root of 21590966 is about 278.4564985716.

The spelling of 21590966 in words is "twenty-one million, five hundred ninety thousand, nine hundred sixty-six".