99979591 has 2 divisors, whose sum is σ = 99979592. Its totient is φ = 99979590.

The previous prime is 99979553. The next prime is 99979603. The reversal of 99979591 is 19597999.

It is a strong prime.

It is an emirp because it is prime and its reverse (19597999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99979591 - 2⁹ = 99979079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99979531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49989795 + 49989796.

It is an arithmetic number, because the mean of its divisors is an integer number (49989796).

Almost surely, 2^99979591 is an apocalyptic number.

99979591 is a deficient number, since it is larger than the sum of its proper divisors (1).

99979591 is an equidigital number, since it uses as much as digits as its factorization.

99979591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2066715, while the sum is 58.

The square root of 99979591 is about 9998.9794979288. The cubic root of 99979591 is about 464.1273044840.

The spelling of 99979591 in words is "ninety-nine million, nine hundred seventy-nine thousand, five hundred ninety-one".