72615440 has 20 divisors (see below), whose sum is σ = 168831084. Its totient is φ = 29046144.

The previous prime is 72615427. The next prime is 72615451. The reversal of 72615440 is 4451627.

It can be written as a sum of positive squares in 2 ways, for example, as 18386944 + 54228496 = 4288^2 + 7364^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 453767 + ... + 453926.

Almost surely, 2^72615440 is an apocalyptic number.

It is an amenable number.

72615440 is an abundant number, since it is smaller than the sum of its proper divisors (96215644).

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

72615440 is a wasteful number, since it uses less digits than its factorization.

72615440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 907706 (or 907700 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 72615440 is about 8521.4693568656. The cubic root of 72615440 is about 417.1987428364.

The spelling of 72615440 in words is "seventy-two million, six hundred fifteen thousand, four hundred forty".