65999328120 has 320 divisors, whose sum is σ = 246107030400. Its totient is φ = 15728152320.

The previous prime is 65999328103. The next prime is 65999328137. The reversal of 65999328120 is 2182399956.

It is a happy number.

65999328120 is a `hidden beast` number, since 6 + 599 + 9 + 3 + 28 + 1 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (65999328103) and next prime (65999328137).

It is a super-2 number, since 2×65999328120² (a number of 22 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 79 ways as a sum of consecutive naturals, for example, 2087067 + ... + 2118453.

It is an arithmetic number, because the mean of its divisors is an integer number (769084470).

Almost surely, 2^65999328120 is an apocalyptic number.

65999328120 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65999328120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123053515200).

65999328120 is an abundant number, since it is smaller than the sum of its proper divisors (180107702280).

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

65999328120 is a wasteful number, since it uses less digits than its factorization.

65999328120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31480 (or 31467 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 65999328120 in words is "sixty-five billion, nine hundred ninety-nine million, three hundred twenty-eight thousand, one hundred twenty".