20777880 has 32 divisors (see below), whose sum is σ = 62334000. Its totient is φ = 5540736.

The previous prime is 20777837. The next prime is 20777899. The reversal of 20777880 is 8877702.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86455 + ... + 86694.

Almost surely, 2^20777880 is an apocalyptic number.

20777880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20777880 is an abundant number, since it is smaller than the sum of its proper divisors (41556120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20777880 is a wasteful number, since it uses less digits than its factorization.

20777880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173163 (or 173159 counting only the distinct ones).

The product of its (nonzero) digits is 43904, while the sum is 39.

The square root of 20777880 is about 4558.2759898892. The cubic root of 20777880 is about 274.9162499790.

It can be divided in two parts, 207 and 77880, that added together give a palindrome (78087).

The spelling of 20777880 in words is "twenty million, seven hundred seventy-seven thousand, eight hundred eighty".