21960985 has 16 divisors (see below), whose sum is σ = 27184896. Its totient is φ = 17022208.

The previous prime is 21960977. The next prime is 21960997. The reversal of 21960985 is 58906912.

It is a cyclic number.

It is not a de Polignac number, because 21960985 - 2³ = 21960977 is a prime.

It is a Duffinian 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, 26142 + ... + 26968.

It is an arithmetic number, because the mean of its divisors is an integer number (1699056).

Almost surely, 2^21960985 is an apocalyptic number.

It is an amenable number.

21960985 is a deficient number, since it is larger than the sum of its proper divisors (5223911).

21960985 is a wasteful number, since it uses less digits than its factorization.

21960985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 21960985 is about 4686.2549013045. The cubic root of 21960985 is about 280.0381963198.

The spelling of 21960985 in words is "twenty-one million, nine hundred sixty thousand, nine hundred eighty-five".