51331553280 has 864 divisors, whose sum is σ = 215126467920. Its totient is φ = 11705057280.

The previous prime is 51331553237. The next prime is 51331553297. The reversal of 51331553280 is 8235513315.

51331553280 is a `hidden beast` number, since 5 + 1 + 33 + 15 + 532 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 121927470 + ... + 121927890.

Almost surely, 2^51331553280 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 51331553280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107563233960).

51331553280 is an abundant number, since it is smaller than the sum of its proper divisors (163794914640).

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

51331553280 is an equidigital number, since it uses as much as digits as its factorization.

51331553280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477 (or 438 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The spelling of 51331553280 in words is "fifty-one billion, three hundred thirty-one million, five hundred fifty-three thousand, two hundred eighty".