51549372864 has 224 divisors, whose sum is σ = 166118926080. Its totient is φ = 15545779200.

The previous prime is 51549372851. The next prime is 51549372869. The reversal of 51549372864 is 46827394515.

It is a happy number.

51549372864 is a `hidden beast` number, since 5 + 1 + 5 + 493 + 72 + 86 + 4 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 51549372864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51549372869) 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, 4004262 + ... + 4017114.

Almost surely, 2^51549372864 is an apocalyptic number.

51549372864 is a gapful number since it is divisible by the number (54) 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 51549372864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83059463040).

51549372864 is an abundant number, since it is smaller than the sum of its proper divisors (114569553216).

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

51549372864 is a wasteful number, since it uses less digits than its factorization.

51549372864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13096 (or 13080 counting only the distinct ones).

The product of its digits is 7257600, while the sum is 54.

The spelling of 51549372864 in words is "fifty-one billion, five hundred forty-nine million, three hundred seventy-two thousand, eight hundred sixty-four".