91436989 has 12 divisors (see below), whose sum is σ = 106521600. Its totient is φ = 78259608.

The previous prime is 91436981. The next prime is 91437013. The reversal of 91436989 is 98963419.

It is not a de Polignac number, because 91436989 - 2³ = 91436981 is a prime.

It is a super-2 number, since 2×91436989² = 16721445914772242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91436981) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61942 + ... + 63400.

It is an arithmetic number, because the mean of its divisors is an integer number (8876800).

Almost surely, 2^91436989 is an apocalyptic number.

It is an amenable number.

91436989 is a deficient number, since it is larger than the sum of its proper divisors (15084611).

91436989 is a wasteful number, since it uses less digits than its factorization.

91436989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2752 (or 2745 counting only the distinct ones).

The product of its digits is 419904, while the sum is 49.

The square root of 91436989 is about 9562.2690298903. The cubic root of 91436989 is about 450.5129771498.

The spelling of 91436989 in words is "ninety-one million, four hundred thirty-six thousand, nine hundred eighty-nine".