51515692740 has 288 divisors, whose sum is σ = 170147134080. Its totient is φ = 12930243840.

The previous prime is 51515692729. The next prime is 51515692757. The reversal of 51515692740 is 4729651515.

It is a happy number.

51515692740 is a `hidden beast` number, since 5 + 1 + 515 + 6 + 92 + 7 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 19199439 + ... + 19202121.

It is an arithmetic number, because the mean of its divisors is an integer number (590788660).

Almost surely, 2^51515692740 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 51515692740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85073567040).

51515692740 is an abundant number, since it is smaller than the sum of its proper divisors (118631441340).

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

51515692740 is a wasteful number, since it uses less digits than its factorization.

51515692740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2800 (or 2761 counting only the distinct ones).

The product of its (nonzero) digits is 378000, while the sum is 45.

The spelling of 51515692740 in words is "fifty-one billion, five hundred fifteen million, six hundred ninety-two thousand, seven hundred forty".