72757440 has 280 divisors, whose sum is σ = 296521632. Its totient is φ = 16588800.

The previous prime is 72757427. The next prime is 72757459. The reversal of 72757440 is 4475727.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (280).

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 = 72757395 and 72757404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 181240 + ... + 181640.

Almost surely, 2^72757440 is an apocalyptic number.

72757440 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 72757440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148260816).

72757440 is an abundant number, since it is smaller than the sum of its proper divisors (223764192).

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

72757440 is a wasteful number, since it uses less digits than its factorization.

72757440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437 (or 418 counting only the distinct ones).

The product of its (nonzero) digits is 54880, while the sum is 36.

The square root of 72757440 is about 8529.7971839898. The cubic root of 72757440 is about 417.4705107836.

The spelling of 72757440 in words is "seventy-two million, seven hundred fifty-seven thousand, four hundred forty".