91643972 has 12 divisors (see below), whose sum is σ = 183288000. Its totient is φ = 39275976.

The previous prime is 91643971. The next prime is 91643977. The reversal of 91643972 is 27934619.

91643972 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (91643971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1636472 + ... + 1636527.

It is an arithmetic number, because the mean of its divisors is an integer number (15274000).

Almost surely, 2^91643972 is an apocalyptic number.

It is an amenable number.

91643972 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91643972 is a wasteful number, since it uses less digits than its factorization.

91643972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3273010 (or 3273008 counting only the distinct ones).

The product of its digits is 81648, while the sum is 41.

The square root of 91643972 is about 9573.0858138847. The cubic root of 91643972 is about 450.8526582631.

The spelling of 91643972 in words is "ninety-one million, six hundred forty-three thousand, nine hundred seventy-two".