51015561504 has 48 divisors (see below), whose sum is σ = 134071241472. Its totient is φ = 16985454848.

The previous prime is 51015561503. The next prime is 51015561517. The reversal of 51015561504 is 40516551015.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (51015561503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 225039 + ... + 390734.

It is an arithmetic number, because the mean of its divisors is an integer number (2793150864).

Almost surely, 2^51015561504 is an apocalyptic number.

It is an amenable number.

51015561504 is an abundant number, since it is smaller than the sum of its proper divisors (83055679968).

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

51015561504 is a wasteful number, since it uses less digits than its factorization.

51015561504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 616649 (or 616641 counting only the distinct ones).

The product of its (nonzero) digits is 15000, while the sum is 33.

The spelling of 51015561504 in words is "fifty-one billion, fifteen million, five hundred sixty-one thousand, five hundred four".