91289969 has 2 divisors, whose sum is σ = 91289970. Its totient is φ = 91289968.

The previous prime is 91289959. The next prime is 91289971. The reversal of 91289969 is 96998219.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 86397025 + 4892944 = 9295^2 + 2212^2 .

It is a cyclic number.

It is not a de Polignac number, because 91289969 - 2⁴ = 91289953 is a prime.

It is a super-2 number, since 2×91289969² = 16667716880041922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 91289971, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 91289969.

It is not a weakly prime, because it can be changed into another prime (91289959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45644984 + 45644985.

It is an arithmetic number, because the mean of its divisors is an integer number (45644985).

Almost surely, 2^91289969 is an apocalyptic number.

It is an amenable number.

91289969 is a deficient number, since it is larger than the sum of its proper divisors (1).

91289969 is an equidigital number, since it uses as much as digits as its factorization.

91289969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 629856, while the sum is 53.

The square root of 91289969 is about 9554.5784313072. The cubic root of 91289969 is about 450.2713902040.

The spelling of 91289969 in words is "ninety-one million, two hundred eighty-nine thousand, nine hundred sixty-nine".