91023689 has 2 divisors, whose sum is σ = 91023690. Its totient is φ = 91023688.

The previous prime is 91023683. The next prime is 91023703. The reversal of 91023689 is 98632019.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77088400 + 13935289 = 8780^2 + 3733^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91023689 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91023683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45511844 + 45511845.

It is an arithmetic number, because the mean of its divisors is an integer number (45511845).

Almost surely, 2^91023689 is an apocalyptic number.

It is an amenable number.

91023689 is a deficient number, since it is larger than the sum of its proper divisors (1).

91023689 is an equidigital number, since it uses as much as digits as its factorization.

91023689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 91023689 is about 9540.6335743492. The cubic root of 91023689 is about 449.8331710808.

The spelling of 91023689 in words is "ninety-one million, twenty-three thousand, six hundred eighty-nine".