20631885 has 16 divisors (see below), whose sum is σ = 33233280. Its totient is φ = 10929600.

The previous prime is 20631869. The next prime is 20631899. The reversal of 20631885 is 58813602.

It is a happy number.

It is not a de Polignac number, because 20631885 - 2⁴ = 20631869 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2290 + ... + 6819.

It is an arithmetic number, because the mean of its divisors is an integer number (2077080).

Almost surely, 2^20631885 is an apocalyptic number.

It is an amenable number.

20631885 is a deficient number, since it is larger than the sum of its proper divisors (12601395).

20631885 is a wasteful number, since it uses less digits than its factorization.

20631885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9268.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 20631885 is about 4542.2334814494. The cubic root of 20631885 is about 274.2708396959.

It can be divided in two parts, 206318 and 85, that added together give a triangular number (206403 = T₆₄₂).

The spelling of 20631885 in words is "twenty million, six hundred thirty-one thousand, eight hundred eighty-five".