91577989 has 8 divisors (see below), whose sum is σ = 93024512. Its totient is φ = 90136800.

The previous prime is 91577987. The next prime is 91578017. The reversal of 91577989 is 98977519.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91577989 - 2¹ = 91577987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91577987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45964 + ... + 47914.

It is an arithmetic number, because the mean of its divisors is an integer number (11628064).

Almost surely, 2^91577989 is an apocalyptic number.

It is an amenable number.

91577989 is a deficient number, since it is larger than the sum of its proper divisors (1446523).

91577989 is a wasteful number, since it uses less digits than its factorization.

91577989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2667.

The product of its digits is 1428840, while the sum is 55.

The square root of 91577989 is about 9569.6389169080. The cubic root of 91577989 is about 450.7444287282.

The spelling of 91577989 in words is "ninety-one million, five hundred seventy-seven thousand, nine hundred eighty-nine".