51768717840 has 640 divisors, whose sum is σ = 221471539200. Its totient is φ = 10846586880.

The previous prime is 51768717823. The next prime is 51768717857. The reversal of 51768717840 is 4871786715.

51768717840 is a `hidden beast` number, since 517 + 6 + 87 + 1 + 7 + 8 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (51768717823) and next prime (51768717857).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 8902774 + ... + 8908586.

It is an arithmetic number, because the mean of its divisors is an integer number (346049280).

Almost surely, 2^51768717840 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 51768717840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110735769600).

51768717840 is an abundant number, since it is smaller than the sum of its proper divisors (169702821360).

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

51768717840 is a wasteful number, since it uses less digits than its factorization.

51768717840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5892 (or 5880 counting only the distinct ones).

The product of its (nonzero) digits is 2634240, while the sum is 54.

The spelling of 51768717840 in words is "fifty-one billion, seven hundred sixty-eight million, seven hundred seventeen thousand, eight hundred forty".