99997609 has 2 divisors, whose sum is σ = 99997610. Its totient is φ = 99997608.

The previous prime is 99997571. The next prime is 99997619. The reversal of 99997609 is 90679999.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99940009 + 57600 = 9997^2 + 240^2 .

It is a cyclic number.

It is not a de Polignac number, because 99997609 - 2¹⁵ = 99964841 is a prime.

It is not a weakly prime, because it can be changed into another prime (99997619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49998804 + 49998805.

It is an arithmetic number, because the mean of its divisors is an integer number (49998805).

Almost surely, 2^99997609 is an apocalyptic number.

It is an amenable number.

99997609 is a deficient number, since it is larger than the sum of its proper divisors (1).

99997609 is an equidigital number, since it uses as much as digits as its factorization.

99997609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2480058, while the sum is 58.

The square root of 99997609 is about 9999.8804492854. The cubic root of 99997609 is about 464.1551839855.

The spelling of 99997609 in words is "ninety-nine million, nine hundred ninety-seven thousand, six hundred nine".