72669561 has 4 divisors (see below), whose sum is σ = 96892752. Its totient is φ = 48446372.

The previous prime is 72669539. The next prime is 72669593. The reversal of 72669561 is 16596627.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72669561 - 2¹⁰ = 72668537 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72669511) 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, 12111591 + ... + 12111596.

It is an arithmetic number, because the mean of its divisors is an integer number (24223188).

Almost surely, 2^72669561 is an apocalyptic number.

It is an amenable number.

72669561 is a deficient number, since it is larger than the sum of its proper divisors (24223191).

72669561 is a wasteful number, since it uses less digits than its factorization.

72669561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24223190.

The product of its digits is 136080, while the sum is 42.

The square root of 72669561 is about 8524.6443327566. The cubic root of 72669561 is about 417.3023645363.

The spelling of 72669561 in words is "seventy-two million, six hundred sixty-nine thousand, five hundred sixty-one".