99572561 has 4 divisors (see below), whose sum is σ = 108624624. Its totient is φ = 90520500.

The previous prime is 99572533. The next prime is 99572569. The reversal of 99572561 is 16527599.

It is a happy number.

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 99572561 - 2¹⁸ = 99310417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99572569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4526015 + ... + 4526036.

It is an arithmetic number, because the mean of its divisors is an integer number (27156156).

Almost surely, 2^99572561 is an apocalyptic number.

It is an amenable number.

99572561 is a deficient number, since it is larger than the sum of its proper divisors (9052063).

99572561 is a wasteful number, since it uses less digits than its factorization.

99572561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9052062.

The product of its digits is 170100, while the sum is 44.

The square root of 99572561 is about 9978.6051630476. The cubic root of 99572561 is about 463.4966068238.

The spelling of 99572561 in words is "ninety-nine million, five hundred seventy-two thousand, five hundred sixty-one".