91970989 has 4 divisors (see below), whose sum is σ = 100332000. Its totient is φ = 83609980.

The previous prime is 91970959. The next prime is 91970999. The reversal of 91970989 is 98907919.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91970989 - 2¹¹ = 91968941 is a prime.

It is a super-3 number, since 3×91970989³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91970959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4180489 + ... + 4180510.

It is an arithmetic number, because the mean of its divisors is an integer number (25083000).

Almost surely, 2^91970989 is an apocalyptic number.

It is an amenable number.

91970989 is a deficient number, since it is larger than the sum of its proper divisors (8361011).

91970989 is a wasteful number, since it uses less digits than its factorization.

91970989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8361010.

The product of its (nonzero) digits is 367416, while the sum is 52.

The square root of 91970989 is about 9590.1506244688. The cubic root of 91970989 is about 451.3882871010.

The spelling of 91970989 in words is "ninety-one million, nine hundred seventy thousand, nine hundred eighty-nine".