691430255 has 32 divisors (see below), whose sum is σ = 885717504. Its totient is φ = 517069696.

The previous prime is 691430227. The next prime is 691430287. The reversal of 691430255 is 552034196.

It is a cyclic number.

It is not a de Polignac number, because 691430255 - 2¹⁴ = 691413871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 1020977 + ... + 1021653.

It is an arithmetic number, because the mean of its divisors is an integer number (27678672).

Almost surely, 2^691430255 is an apocalyptic number.

691430255 is a deficient number, since it is larger than the sum of its proper divisors (194287249).

691430255 is a wasteful number, since it uses less digits than its factorization.

691430255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 691430255 is about 26295.0614184489. The cubic root of 691430255 is about 884.2657277868.

The spelling of 691430255 in words is "six hundred ninety-one million, four hundred thirty thousand, two hundred fifty-five".