655705991 has 2 divisors, whose sum is σ = 655705992. Its totient is φ = 655705990.

The previous prime is 655705969. The next prime is 655706021. The reversal of 655705991 is 199507556.

655705991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 655705991 - 2¹⁸ = 655443847 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 (655705901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327852995 + 327852996.

It is an arithmetic number, because the mean of its divisors is an integer number (327852996).

Almost surely, 2^655705991 is an apocalyptic number.

655705991 is a deficient number, since it is larger than the sum of its proper divisors (1).

655705991 is an equidigital number, since it uses as much as digits as its factorization.

655705991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 425250, while the sum is 47.

The square root of 655705991 is about 25606.7567450468. The cubic root of 655705991 is about 868.7664691528.

The spelling of 655705991 in words is "six hundred fifty-five million, seven hundred five thousand, nine hundred ninety-one".