20887780 has 24 divisors (see below), whose sum is σ = 44396352. Its totient is φ = 8253792.

The previous prime is 20887759. The next prime is 20887793. The reversal of 20887780 is 8778802.

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, 4632 + ... + 7951.

It is an arithmetic number, because the mean of its divisors is an integer number (1849848).

Almost surely, 2^20887780 is an apocalyptic number.

20887780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20887780 is an abundant number, since it is smaller than the sum of its proper divisors (23508572).

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

20887780 is a wasteful number, since it uses less digits than its factorization.

20887780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12675 (or 12673 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 40.

The square root of 20887780 is about 4570.3150876061. The cubic root of 20887780 is about 275.4001008018.

The spelling of 20887780 in words is "twenty million, eight hundred eighty-seven thousand, seven hundred eighty".