20953985 has 16 divisors (see below), whose sum is σ = 27955200. Its totient is φ = 14973120.

The previous prime is 20953973. The next prime is 20953997. The reversal of 20953985 is 58935902.

It is an interprime number because it is at equal distance from previous prime (20953973) and next prime (20953997).

It is not a de Polignac number, because 20953985 - 2⁴ = 20953969 is a prime.

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, 3185 + ... + 7214.

It is an arithmetic number, because the mean of its divisors is an integer number (1747200).

Almost surely, 2^20953985 is an apocalyptic number.

It is an amenable number.

20953985 is a deficient number, since it is larger than the sum of its proper divisors (7001215).

20953985 is a wasteful number, since it uses less digits than its factorization.

20953985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10448.

The product of its (nonzero) digits is 97200, while the sum is 41.

The square root of 20953985 is about 4577.5522935298. The cubic root of 20953985 is about 275.6907593297.

The spelling of 20953985 in words is "twenty million, nine hundred fifty-three thousand, nine hundred eighty-five".