91318687 has 2 divisors, whose sum is σ = 91318688. Its totient is φ = 91318686.

The previous prime is 91318681. The next prime is 91318739. The reversal of 91318687 is 78681319.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91318687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91318681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45659343 + 45659344.

It is an arithmetic number, because the mean of its divisors is an integer number (45659344).

Almost surely, 2^91318687 is an apocalyptic number.

91318687 is a deficient number, since it is larger than the sum of its proper divisors (1).

91318687 is an equidigital number, since it uses as much as digits as its factorization.

91318687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 43.

The square root of 91318687 is about 9556.0811528576. The cubic root of 91318687 is about 450.3186007144.

It can be divided in two parts, 913 and 18687, that added together give a square (19600 = 140²).

The spelling of 91318687 in words is "ninety-one million, three hundred eighteen thousand, six hundred eighty-seven".