51322565640 has 32 divisors (see below), whose sum is σ = 153967697280. Its totient is φ = 13686017472.

The previous prime is 51322565611. The next prime is 51322565641. The reversal of 51322565640 is 4656522315.

It is not an unprimeable number, because it can be changed into a prime (51322565641) 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, 213843904 + ... + 213844143.

It is an arithmetic number, because the mean of its divisors is an integer number (4811490540).

Almost surely, 2^51322565640 is an apocalyptic number.

It is an amenable number.

51322565640 is an abundant number, since it is smaller than the sum of its proper divisors (102645131640).

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

51322565640 is a wasteful number, since it uses less digits than its factorization.

51322565640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427688061 (or 427688057 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

The spelling of 51322565640 in words is "fifty-one billion, three hundred twenty-two million, five hundred sixty-five thousand, six hundred forty".