51155501664 has 48 divisors (see below), whose sum is σ = 138913654320. Its totient is φ = 16463838720.

The previous prime is 51155501627. The next prime is 51155501689. The reversal of 51155501664 is 46610555115.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9184627 + ... + 9190194.

It is an arithmetic number, because the mean of its divisors is an integer number (2894034465).

Almost surely, 2^51155501664 is an apocalyptic number.

It is an amenable number.

51155501664 is an abundant number, since it is smaller than the sum of its proper divisors (87758152656).

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

51155501664 is a wasteful number, since it uses less digits than its factorization.

51155501664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18374863 (or 18374855 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 39.

The spelling of 51155501664 in words is "fifty-one billion, one hundred fifty-five million, five hundred one thousand, six hundred sixty-four".