51378228720 has 960 divisors, whose sum is σ = 224921854080. Its totient is φ = 10816727040.

The previous prime is 51378228709. The next prime is 51378228721. The reversal of 51378228720 is 2782287315.

51378228720 is a `hidden beast` number, since 51 + 378 + 228 + 7 + 2 + 0 = 666.

It is a super-3 number, since 3×51378228720³ (a number of 33 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51378228721) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 111449290 + ... + 111449750.

It is an arithmetic number, because the mean of its divisors is an integer number (234293598).

Almost surely, 2^51378228720 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 51378228720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112460927040).

51378228720 is an abundant number, since it is smaller than the sum of its proper divisors (173543625360).

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

51378228720 is a wasteful number, since it uses less digits than its factorization.

51378228720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 522 (or 491 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 51378228720 in words is "fifty-one billion, three hundred seventy-eight million, two hundred twenty-eight thousand, seven hundred twenty".