99975509 has 2 divisors, whose sum is σ = 99975510. Its totient is φ = 99975508.

The previous prime is 99975497. The next prime is 99975529. The reversal of 99975509 is 90557999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91107025 + 8868484 = 9545^2 + 2978^2 .

It is a cyclic number.

It is not a de Polignac number, because 99975509 - 2⁴ = 99975493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99975529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49987754 + 49987755.

It is an arithmetic number, because the mean of its divisors is an integer number (49987755).

Almost surely, 2^99975509 is an apocalyptic number.

It is an amenable number.

99975509 is a deficient number, since it is larger than the sum of its proper divisors (1).

99975509 is an equidigital number, since it uses as much as digits as its factorization.

99975509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1148175, while the sum is 53.

The square root of 99975509 is about 9998.7753750147. The cubic root of 99975509 is about 464.1209878834.

The spelling of 99975509 in words is "ninety-nine million, nine hundred seventy-five thousand, five hundred nine".