72981338640 has 320 divisors, whose sum is σ = 285677715456. Its totient is φ = 15017435136.

The previous prime is 72981338621. The next prime is 72981338641. The reversal of 72981338640 is 4683318927.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (72981338641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 601329 + ... + 712431.

Almost surely, 2^72981338640 is an apocalyptic number.

72981338640 is a gapful number since it is divisible by the number (70) 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 72981338640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142838857728).

72981338640 is an abundant number, since it is smaller than the sum of its proper divisors (212696376816).

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

72981338640 is a wasteful number, since it uses less digits than its factorization.

72981338640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111166 (or 111160 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 51.

The spelling of 72981338640 in words is "seventy-two billion, nine hundred eighty-one million, three hundred thirty-eight thousand, six hundred forty".