815900880 has 80 divisors (see below), whose sum is σ = 2532070080. Its totient is φ = 217334784.

The previous prime is 815900863. The next prime is 815900887. The reversal of 815900880 is 88009518.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815900887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 377884 + ... + 380036.

It is an arithmetic number, because the mean of its divisors is an integer number (31650876).

Almost surely, 2^815900880 is an apocalyptic number.

815900880 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

815900880 is an abundant number, since it is smaller than the sum of its proper divisors (1716169200).

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

815900880 is a wasteful number, since it uses less digits than its factorization.

815900880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3748 (or 3742 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 39.

The square root of 815900880 is about 28563.9787144578. The cubic root of 815900880 is about 934.4279074377.

The spelling of 815900880 in words is "eight hundred fifteen million, nine hundred thousand, eight hundred eighty".