51497979780 has 96 divisors (see below), whose sum is σ = 155835598464. Its totient is φ = 12631578624.

The previous prime is 51497979749. The next prime is 51497979781. The reversal of 51497979780 is 8797979415.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (51497979781) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104092 + ... + 337388.

It is an arithmetic number, because the mean of its divisors is an integer number (1623287484).

Almost surely, 2^51497979780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51497979780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77917799232).

51497979780 is an abundant number, since it is smaller than the sum of its proper divisors (104337618684).

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

51497979780 is a wasteful number, since it uses less digits than its factorization.

51497979780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233605 (or 233603 counting only the distinct ones).

The product of its (nonzero) digits is 40007520, while the sum is 66.

The spelling of 51497979780 in words is "fifty-one billion, four hundred ninety-seven million, nine hundred seventy-nine thousand, seven hundred eighty".