99566639 has 2 divisors, whose sum is σ = 99566640. Its totient is φ = 99566638.

The previous prime is 99566591. The next prime is 99566641. The reversal of 99566639 is 93666599.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99566639 is a prime.

It is a Sophie Germain prime.

Together with 99566641, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99566659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49783319 + 49783320.

It is an arithmetic number, because the mean of its divisors is an integer number (49783320).

Almost surely, 2^99566639 is an apocalyptic number.

99566639 is a deficient number, since it is larger than the sum of its proper divisors (1).

99566639 is an equidigital number, since it uses as much as digits as its factorization.

99566639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2361960, while the sum is 53.

The square root of 99566639 is about 9978.3084237760. The cubic root of 99566639 is about 463.4874179426.

The spelling of 99566639 in words is "ninety-nine million, five hundred sixty-six thousand, six hundred thirty-nine".