72561630 has 16 divisors (see below), whose sum is σ = 174147984. Its totient is φ = 19349760.

The previous prime is 72561613. The next prime is 72561641. The reversal of 72561630 is 3616527.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 2418721 = 72561630 / (7 + 2 + 5 + 6 + 1 + 6 + 3 + 0).

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1209331 + ... + 1209390.

It is an arithmetic number, because the mean of its divisors is an integer number (10884249).

Almost surely, 2^72561630 is an apocalyptic number.

72561630 is an abundant number, since it is smaller than the sum of its proper divisors (101586354).

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

72561630 is a wasteful number, since it uses less digits than its factorization.

72561630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2418731.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 72561630 is about 8518.3114523948. The cubic root of 72561630 is about 417.0956655301.

The spelling of 72561630 in words is "seventy-two million, five hundred sixty-one thousand, six hundred thirty".