72705440 has 24 divisors (see below), whose sum is σ = 171766980. Its totient is φ = 29082112.

The previous prime is 72705403. The next prime is 72705449. The reversal of 72705440 is 4450727.

It can be written as a sum of positive squares in 2 ways, for example, as 72522256 + 183184 = 8516^2 + 428^2 .

It is not an unprimeable number, because it can be changed into a prime (72705449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 227045 + ... + 227364.

Almost surely, 2^72705440 is an apocalyptic number.

It is an amenable number.

72705440 is an abundant number, since it is smaller than the sum of its proper divisors (99061540).

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

72705440 is a wasteful number, since it uses less digits than its factorization.

72705440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454424 (or 454416 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 29.

The square root of 72705440 is about 8526.7485010407. The cubic root of 72705440 is about 417.3710311963.

The spelling of 72705440 in words is "seventy-two million, seven hundred five thousand, four hundred forty".