91163609 has 2 divisors, whose sum is σ = 91163610. Its totient is φ = 91163608.

The previous prime is 91163603. The next prime is 91163621. The reversal of 91163609 is 90636119.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75203584 + 15960025 = 8672^2 + 3995^2 .

It is a cyclic number.

It is not a de Polignac number, because 91163609 - 2⁸ = 91163353 is a prime.

It is not a weakly prime, because it can be changed into another prime (91163603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45581804 + 45581805.

It is an arithmetic number, because the mean of its divisors is an integer number (45581805).

Almost surely, 2^91163609 is an apocalyptic number.

It is an amenable number.

91163609 is a deficient number, since it is larger than the sum of its proper divisors (1).

91163609 is an equidigital number, since it uses as much as digits as its factorization.

91163609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 91163609 is about 9547.9636048741. The cubic root of 91163609 is about 450.0635449358.

The spelling of 91163609 in words is "ninety-one million, one hundred sixty-three thousand, six hundred nine".