72309032640 has 896 divisors, whose sum is σ = 298772275200. Its totient is φ = 16303472640.

The previous prime is 72309032617. The next prime is 72309032657. The reversal of 72309032640 is 4623090327.

It is a happy number.

72309032640 is a `hidden beast` number, since 7 + 2 + 3 + 0 + 9 + 0 + 3 + 2 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 72309032595 and 72309032604.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 66155934 + ... + 66157026.

It is an arithmetic number, because the mean of its divisors is an integer number (333451200).

Almost surely, 2^72309032640 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 72309032640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149386137600).

72309032640 is an abundant number, since it is smaller than the sum of its proper divisors (226463242560).

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

72309032640 is a wasteful number, since it uses less digits than its factorization.

72309032640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1182 (or 1166 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 36.

The spelling of 72309032640 in words is "seventy-two billion, three hundred nine million, thirty-two thousand, six hundred forty".