68611591 has 2 divisors, whose sum is σ = 68611592. Its totient is φ = 68611590.

The previous prime is 68611567. The next prime is 68611597. The reversal of 68611591 is 19511686.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 68611591 - 2⁵ = 68611559 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 68611591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68611597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34305795 + 34305796.

It is an arithmetic number, because the mean of its divisors is an integer number (34305796).

Almost surely, 2^68611591 is an apocalyptic number.

68611591 is a deficient number, since it is larger than the sum of its proper divisors (1).

68611591 is an equidigital number, since it uses as much as digits as its factorization.

68611591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 37.

The square root of 68611591 is about 8283.2113941394. The cubic root of 68611591 is about 409.3855380307.

It can be divided in two parts, 686115 and 91, that added together give a triangular number (686206 = T₁₁₇₁).

The spelling of 68611591 in words is "sixty-eight million, six hundred eleven thousand, five hundred ninety-one".