91651187 has 2 divisors, whose sum is σ = 91651188. Its totient is φ = 91651186.

The previous prime is 91651181. The next prime is 91651211. The reversal of 91651187 is 78115619.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91651187 - 2¹⁶ = 91585651 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91651187.

It is not a weakly prime, because it can be changed into another prime (91651181) 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, 45825593 + 45825594.

It is an arithmetic number, because the mean of its divisors is an integer number (45825594).

Almost surely, 2^91651187 is an apocalyptic number.

91651187 is a deficient number, since it is larger than the sum of its proper divisors (1).

91651187 is an equidigital number, since it uses as much as digits as its factorization.

91651187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15120, while the sum is 38.

The square root of 91651187 is about 9573.4626442056. The cubic root of 91651187 is about 450.8644896162.

The spelling of 91651187 in words is "ninety-one million, six hundred fifty-one thousand, one hundred eighty-seven".