816524640 has 72 divisors (see below), whose sum is σ = 2786395248. Its totient is φ = 217739520.

The previous prime is 816524573. The next prime is 816524647. The reversal of 816524640 is 46425618.

816524640 is a `hidden beast` number, since 8 + 1 + 6 + 5 + 2 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 816524595 and 816524604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816524647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 282076 + ... + 284955.

It is an arithmetic number, because the mean of its divisors is an integer number (38699934).

Almost surely, 2^816524640 is an apocalyptic number.

816524640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

816524640 is an abundant number, since it is smaller than the sum of its proper divisors (1969870608).

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

816524640 is a wasteful number, since it uses less digits than its factorization.

816524640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 567052 (or 567041 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 816524640 is about 28574.8952753986. The cubic root of 816524640 is about 934.6659716013.

The spelling of 816524640 in words is "eight hundred sixteen million, five hundred twenty-four thousand, six hundred forty".