72731173320 has 384 divisors, whose sum is σ = 265827744000. Its totient is φ = 17778299904.

The previous prime is 72731173313. The next prime is 72731173363. The reversal of 72731173320 is 2337113727.

72731173320 is a `hidden beast` number, since 7 + 2 + 7 + 311 + 7 + 332 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18825709 + ... + 18829571.

It is an arithmetic number, because the mean of its divisors is an integer number (692259750).

Almost surely, 2^72731173320 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 72731173320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132913872000).

72731173320 is an abundant number, since it is smaller than the sum of its proper divisors (193096570680).

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

72731173320 is a wasteful number, since it uses less digits than its factorization.

72731173320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4051 (or 4035 counting only the distinct ones).

The product of its (nonzero) digits is 37044, while the sum is 36.

It can be divided in two parts, 72731 and 173320, that added together give a triangular number (246051 = T₇₀₁).

The spelling of 72731173320 in words is "seventy-two billion, seven hundred thirty-one million, one hundred seventy-three thousand, three hundred twenty".