815556960 has 144 divisors (see below), whose sum is σ = 2858493456. Its totient is φ = 211590144.

The previous prime is 815556943. The next prime is 815556961. The reversal of 815556960 is 69655518.

It is a happy number.

815556960 is a `hidden beast` number, since 8 + 1 + 5 + 556 + 96 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-3 number, since 3×815556960³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815556961) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45627 + ... + 60933.

It is an arithmetic number, because the mean of its divisors is an integer number (19850649).

Almost surely, 2^815556960 is an apocalyptic number.

815556960 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 815556960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1429246728).

815556960 is an abundant number, since it is smaller than the sum of its proper divisors (2042936496).

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

815556960 is a wasteful number, since it uses less digits than its factorization.

815556960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15365 (or 15354 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 45.

The square root of 815556960 is about 28557.9579101868. The cubic root of 815556960 is about 934.2965950773.

The spelling of 815556960 in words is "eight hundred fifteen million, five hundred fifty-six thousand, nine hundred sixty".