51133249728 has 224 divisors, whose sum is σ = 166017488640. Its totient is φ = 15494457600.

The previous prime is 51133249721. The next prime is 51133249729. The reversal of 51133249728 is 82794233115.

It is a happy number.

51133249728 is a `hidden beast` number, since 5 + 1 + 133 + 2 + 497 + 28 = 666.

It is a super-2 number, since 2×51133249728² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51133249721) 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, 1523043 + ... + 1556253.

Almost surely, 2^51133249728 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 51133249728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83008744320).

51133249728 is an abundant number, since it is smaller than the sum of its proper divisors (114884238912).

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

51133249728 is an equidigital number, since it uses as much as digits as its factorization.

51133249728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33255 (or 33227 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The spelling of 51133249728 in words is "fifty-one billion, one hundred thirty-three million, two hundred forty-nine thousand, seven hundred twenty-eight".