99920565 has 12 divisors (see below), whose sum is σ = 173195724. Its totient is φ = 53290944.

The previous prime is 99920549. The next prime is 99920581. The reversal of 99920565 is 56502999.

It is an interprime number because it is at equal distance from previous prime (99920549) and next prime (99920581).

It can be written as a sum of positive squares in 2 ways, for example, as 33628401 + 66292164 = 5799^2 + 8142^2 .

It is not a de Polignac number, because 99920565 - 2⁴ = 99920549 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 2220457 = 99920565 / (9 + 9 + 9 + 2 + 0 + 5 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 99920565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1110184 + ... + 1110273.

It is an arithmetic number, because the mean of its divisors is an integer number (14432977).

Almost surely, 2^99920565 is an apocalyptic number.

It is an amenable number.

99920565 is a deficient number, since it is larger than the sum of its proper divisors (73275159).

99920565 is a wasteful number, since it uses less digits than its factorization.

99920565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2220468 (or 2220465 counting only the distinct ones).

The product of its (nonzero) digits is 218700, while the sum is 45.

The square root of 99920565 is about 9996.0274609467. The cubic root of 99920565 is about 464.0359492683.

The spelling of 99920565 in words is "ninety-nine million, nine hundred twenty thousand, five hundred sixty-five".