51685977600 has 720 divisors, whose sum is σ = 196147695744. Its totient is φ = 12976128000.

The previous prime is 51685977587. The next prime is 51685977613. The reversal of 51685977600 is 677958615.

51685977600 is a `hidden beast` number, since 516 + 8 + 59 + 7 + 76 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (51685977587) and next prime (51685977613).

It is a tau number, because it is divible by the number of its divisors (720).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 146419024 + ... + 146419376.

Almost surely, 2^51685977600 is an apocalyptic number.

51685977600 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51685977600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98073847872).

51685977600 is an abundant number, since it is smaller than the sum of its proper divisors (144461718144).

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

51685977600 is a wasteful number, since it uses less digits than its factorization.

51685977600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 435 counting only the distinct ones).

The product of its (nonzero) digits is 3175200, while the sum is 54.

The spelling of 51685977600 in words is "fifty-one billion, six hundred eighty-five million, nine hundred seventy-seven thousand, six hundred".