99689321 has 2 divisors, whose sum is σ = 99689322. Its totient is φ = 99689320.

The previous prime is 99689299. The next prime is 99689339. The reversal of 99689321 is 12398699.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70744921 + 28944400 = 8411^2 + 5380^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99689321 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (99689221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49844660 + 49844661.

It is an arithmetic number, because the mean of its divisors is an integer number (49844661).

Almost surely, 2^99689321 is an apocalyptic number.

It is an amenable number.

99689321 is a deficient number, since it is larger than the sum of its proper divisors (1).

99689321 is an equidigital number, since it uses as much as digits as its factorization.

99689321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 47.

The square root of 99689321 is about 9984.4539660414. The cubic root of 99689321 is about 463.6777033158.

The spelling of 99689321 in words is "ninety-nine million, six hundred eighty-nine thousand, three hundred twenty-one".