72530640 has 480 divisors, whose sum is σ = 318479616. Its totient is φ = 14929920.

The previous prime is 72530603. The next prime is 72530651. The reversal of 72530640 is 4603527.

72530640 = 1310² + 1311² + ... + 1350².

It is a happy number.

72530640 is a `hidden beast` number, since 72 + 530 + 64 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

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, 1769020 + ... + 1769060.

Almost surely, 2^72530640 is an apocalyptic number.

72530640 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 72530640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159239808).

72530640 is an abundant number, since it is smaller than the sum of its proper divisors (245948976).

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

72530640 is a wasteful number, since it uses less digits than its factorization.

72530640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 27.

The square root of 72530640 is about 8516.4922356566. The cubic root of 72530640 is about 417.0362786097.

The spelling of 72530640 in words is "seventy-two million, five hundred thirty thousand, six hundred forty".