51765665328 has 300 divisors, whose sum is σ = 163601695488. Its totient is φ = 15793989120.

The previous prime is 51765665317. The next prime is 51765665339. The reversal of 51765665328 is 82356656715.

It is a happy number.

51765665328 is a `hidden beast` number, since 5 + 1 + 7 + 6 + 566 + 53 + 28 = 666.

It is an interprime number because it is at equal distance from previous prime (51765665317) and next prime (51765665339).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 27815118 + ... + 27816978.

Almost surely, 2^51765665328 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 51765665328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81800847744).

51765665328 is an abundant number, since it is smaller than the sum of its proper divisors (111836030160).

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

51765665328 is a wasteful number, since it uses less digits than its factorization.

51765665328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2034 (or 2006 counting only the distinct ones).

The product of its digits is 9072000, while the sum is 54.

The spelling of 51765665328 in words is "fifty-one billion, seven hundred sixty-five million, six hundred sixty-five thousand, three hundred twenty-eight".