814997520 has 120 divisors (see below), whose sum is σ = 2811099096. Its totient is φ = 211451904.

The previous prime is 814997509. The next prime is 814997537. The reversal of 814997520 is 25799418.

814997520 is a `hidden beast` number, since 81 + 49 + 9 + 7 + 520 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 290770704 + 524226816 = 17052^2 + 22896^2 .

It is a tau number, because it is divible by the number of its divisors (120).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11344 + ... + 41936.

Almost surely, 2^814997520 is an apocalyptic number.

814997520 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 814997520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1405549548).

814997520 is an abundant number, since it is smaller than the sum of its proper divisors (1996101576).

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

814997520 is a wasteful number, since it uses less digits than its factorization.

814997520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30649 (or 30640 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The square root of 814997520 is about 28548.1614119018. The cubic root of 814997520 is about 934.0829159714.

The spelling of 814997520 in words is "eight hundred fourteen million, nine hundred ninety-seven thousand, five hundred twenty".