20880987 has 16 divisors (see below), whose sum is σ = 29840640. Its totient is φ = 12953952.

The previous prime is 20880973. The next prime is 20880989. The reversal of 20880987 is 78908802.

It is a happy number.

It is not a de Polignac number, because 20880987 - 2⁸ = 20880731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20880989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1537 + ... + 6642.

It is an arithmetic number, because the mean of its divisors is an integer number (1865040).

Almost surely, 2^20880987 is an apocalyptic number.

20880987 is a deficient number, since it is larger than the sum of its proper divisors (8959653).

20880987 is a wasteful number, since it uses less digits than its factorization.

20880987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8242.

The product of its (nonzero) digits is 64512, while the sum is 42.

The square root of 20880987 is about 4569.5718617831. The cubic root of 20880987 is about 275.3702429021.

The spelling of 20880987 in words is "twenty million, eight hundred eighty thousand, nine hundred eighty-seven".