991704407 has 2 divisors, whose sum is σ = 991704408. Its totient is φ = 991704406.

The previous prime is 991704383. The next prime is 991704419. The reversal of 991704407 is 704407199.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991704407 - 2⁸ = 991704151 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991704437) 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, 495852203 + 495852204.

It is an arithmetic number, because the mean of its divisors is an integer number (495852204).

Almost surely, 2^991704407 is an apocalyptic number.

991704407 is a deficient number, since it is larger than the sum of its proper divisors (1).

991704407 is an equidigital number, since it uses as much as digits as its factorization.

991704407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 63504, while the sum is 41.

The square root of 991704407 is about 31491.3386028603. The cubic root of 991704407 is about 997.2271205798.

The spelling of 991704407 in words is "nine hundred ninety-one million, seven hundred four thousand, four hundred seven".