515815464864 has 96 divisors (see below), whose sum is σ = 1597364084736. Its totient is φ = 142621781760.

The previous prime is 515815464863. The next prime is 515815464881. The reversal of 515815464864 is 468464518515.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (515815464863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12359532 + ... + 12401195.

It is an arithmetic number, because the mean of its divisors is an integer number (16639209216).

Almost surely, 2^515815464864 is an apocalyptic number.

It is an amenable number.

515815464864 is an abundant number, since it is smaller than the sum of its proper divisors (1081548619872).

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

515815464864 is a wasteful number, since it uses less digits than its factorization.

515815464864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24760778 (or 24760770 counting only the distinct ones).

The product of its digits is 18432000, while the sum is 57.

The spelling of 515815464864 in words is "five hundred fifteen billion, eight hundred fifteen million, four hundred sixty-four thousand, eight hundred sixty-four".