91758649 has 2 divisors, whose sum is σ = 91758650. Its totient is φ = 91758648.

The previous prime is 91758613. The next prime is 91758679. The reversal of 91758649 is 94685719.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71571600 + 20187049 = 8460^2 + 4493^2 .

It is a cyclic number.

It is not a de Polignac number, because 91758649 - 2⁹ = 91758137 is a prime.

It is not a weakly prime, because it can be changed into another prime (91758679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45879324 + 45879325.

It is an arithmetic number, because the mean of its divisors is an integer number (45879325).

Almost surely, 2^91758649 is an apocalyptic number.

It is an amenable number.

91758649 is a deficient number, since it is larger than the sum of its proper divisors (1).

91758649 is an equidigital number, since it uses as much as digits as its factorization.

91758649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 91758649 is about 9579.0734938197. The cubic root of 91758649 is about 451.0406352735.

The spelling of 91758649 in words is "ninety-one million, seven hundred fifty-eight thousand, six hundred forty-nine".