691592399 has 2 divisors, whose sum is σ = 691592400. Its totient is φ = 691592398.

The previous prime is 691592383. The next prime is 691592401. The reversal of 691592399 is 993295196.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 691592399 - 2⁴ = 691592383 is a prime.

Together with 691592401, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 691592399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691592309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345796199 + 345796200.

It is an arithmetic number, because the mean of its divisors is an integer number (345796200).

Almost surely, 2^691592399 is an apocalyptic number.

691592399 is a deficient number, since it is larger than the sum of its proper divisors (1).

691592399 is an equidigital number, since it uses as much as digits as its factorization.

691592399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1180980, while the sum is 53.

The square root of 691592399 is about 26298.1444022197. The cubic root of 691592399 is about 884.3348440257.

The spelling of 691592399 in words is "six hundred ninety-one million, five hundred ninety-two thousand, three hundred ninety-nine".