21996715 has 8 divisors (see below), whose sum is σ = 28426608. Its totient is φ = 16243680.

The previous prime is 21996707. The next prime is 21996727. The reversal of 21996715 is 51769912.

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

It is not a de Polignac number, because 21996715 - 2³ = 21996707 is a prime.

It is a Duffinian number.

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, 169141 + ... + 169270.

It is an arithmetic number, because the mean of its divisors is an integer number (3553326).

Almost surely, 2^21996715 is an apocalyptic number.

21996715 is a deficient number, since it is larger than the sum of its proper divisors (6429893).

21996715 is a wasteful number, since it uses less digits than its factorization.

21996715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338429.

The product of its digits is 34020, while the sum is 40.

The square root of 21996715 is about 4690.0655645737. The cubic root of 21996715 is about 280.1899858574.

The spelling of 21996715 in words is "twenty-one million, nine hundred ninety-six thousand, seven hundred fifteen".