72569621 has 4 divisors (see below), whose sum is σ = 73385100. Its totient is φ = 71754144.

The previous prime is 72569603. The next prime is 72569641. The reversal of 72569621 is 12696527.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3845521 + 68724100 = 1961^2 + 8290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72569621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72569641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 407606 + ... + 407783.

It is an arithmetic number, because the mean of its divisors is an integer number (18346275).

Almost surely, 2^72569621 is an apocalyptic number.

It is an amenable number.

72569621 is a deficient number, since it is larger than the sum of its proper divisors (815479).

72569621 is an equidigital number, since it uses as much as digits as its factorization.

72569621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815478.

The product of its digits is 45360, while the sum is 38.

The square root of 72569621 is about 8518.7804878398. The cubic root of 72569621 is about 417.1109761432.

The spelling of 72569621 in words is "seventy-two million, five hundred sixty-nine thousand, six hundred twenty-one".