51118028881920 has 4560 divisors, whose sum is σ = 254104074753408. Its totient is φ = 9539860561920.

The previous prime is 51118028881903. The next prime is 51118028881981. The reversal of 51118028881920 is 2918882081115.

51118028881920 is a `hidden beast` number, since 511 + 1 + 8 + 0 + 28 + 8 + 81 + 9 + 20 = 666.

It is a super-2 number, since 2×51118028881920² (a number of 28 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 1381568348142 + ... + 1381568348178.

Almost surely, 2^{51118028881920} 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 51118028881920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127052037376704).

51118028881920 is an abundant number, since it is smaller than the sum of its proper divisors (202986045871488).

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

51118028881920 is an equidigital number, since it uses as much as digits as its factorization.

51118028881920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 54.

The spelling of 51118028881920 in words is "fifty-one trillion, one hundred eighteen billion, twenty-eight million, eight hundred eighty-one thousand, nine hundred twenty".