51465006440 has 64 divisors (see below), whose sum is σ = 125921595600. Its totient is φ = 18851401728.

The previous prime is 51465006433. The next prime is 51465006443. The reversal of 51465006440 is 4460056415.

It can be written as a sum of positive squares in 8 ways, for example, as 49926327364 + 1538679076 = 223442^2 + 39226^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51465006440.

It is not an unprimeable number, because it can be changed into a prime (51465006443) 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, 997595 + ... + 1047914.

Almost surely, 2^51465006440 is an apocalyptic number.

It is an amenable number.

51465006440 is an abundant number, since it is smaller than the sum of its proper divisors (74456589160).

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

51465006440 is a wasteful number, since it uses less digits than its factorization.

51465006440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2045574 (or 2045570 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The spelling of 51465006440 in words is "fifty-one billion, four hundred sixty-five million, six thousand, four hundred forty".