72542556 has 18 divisors (see below), whose sum is σ = 183371552. Its totient is φ = 24180840.

The previous prime is 72542521. The next prime is 72542557. The reversal of 72542556 is 65524527.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2015071 = 72542556 / (7 + 2 + 5 + 4 + 2 + 5 + 5 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 72542556.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72542557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1007500 + ... + 1007571.

Almost surely, 2^72542556 is an apocalyptic number.

It is an amenable number.

72542556 is an abundant number, since it is smaller than the sum of its proper divisors (110828996).

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

72542556 is a wasteful number, since it uses less digits than its factorization.

72542556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2015081 (or 2015076 counting only the distinct ones).

The product of its digits is 84000, while the sum is 36.

The square root of 72542556 is about 8517.1917907254. The cubic root of 72542556 is about 417.0591155430.

The spelling of 72542556 in words is "seventy-two million, five hundred forty-two thousand, five hundred fifty-six".