51681988280 has 32 divisors (see below), whose sum is σ = 125229434400. Its totient is φ = 19082580096.

The previous prime is 51681988261. The next prime is 51681988289. The reversal of 51681988280 is 8288918615.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51681988289) 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, 49693700 + ... + 49694739.

It is an arithmetic number, because the mean of its divisors is an integer number (3913419825).

Almost surely, 2^51681988280 is an apocalyptic number.

It is an amenable number.

51681988280 is an abundant number, since it is smaller than the sum of its proper divisors (73547446120).

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

51681988280 is a wasteful number, since it uses less digits than its factorization.

51681988280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99388463 (or 99388459 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 56.

The spelling of 51681988280 in words is "fifty-one billion, six hundred eighty-one million, nine hundred eighty-eight thousand, two hundred eighty".