51785792640 has 512 divisors, whose sum is σ = 190552320000. Its totient is φ = 13277675520.

The previous prime is 51785792603. The next prime is 51785792687. The reversal of 51785792640 is 4629758715.

51785792640 is a `hidden beast` number, since 5 + 1 + 7 + 8 + 579 + 2 + 64 + 0 = 666.

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 63 ways as a sum of consecutive naturals, for example, 148383186 + ... + 148383534.

It is an arithmetic number, because the mean of its divisors is an integer number (372172500).

Almost surely, 2^51785792640 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 51785792640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95276160000).

51785792640 is an abundant number, since it is smaller than the sum of its proper divisors (138766527360).

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

51785792640 is a wasteful number, since it uses less digits than its factorization.

51785792640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 4233600, while the sum is 54.

The spelling of 51785792640 in words is "fifty-one billion, seven hundred eighty-five million, seven hundred ninety-two thousand, six hundred forty".