21907966 has 8 divisors (see below), whose sum is σ = 33009984. Its totient is φ = 10904640.

The previous prime is 21907961. The next prime is 21908039. The reversal of 21907966 is 66970912.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21907961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24115 + ... + 25006.

It is an arithmetic number, because the mean of its divisors is an integer number (4126248).

Almost surely, 2^21907966 is an apocalyptic number.

21907966 is a deficient number, since it is larger than the sum of its proper divisors (11102018).

21907966 is a wasteful number, since it uses less digits than its factorization.

21907966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49346.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 21907966 is about 4680.5946203447. The cubic root of 21907966 is about 279.8126552901.

The spelling of 21907966 in words is "twenty-one million, nine hundred seven thousand, nine hundred sixty-six".