91281432 has 144 divisors (see below), whose sum is σ = 271910520. Its totient is φ = 25428480.

The previous prime is 91281431. The next prime is 91281433. The reversal of 91281432 is 23418219.

It is an interprime number because it is at equal distance from previous prime (91281431) and next prime (91281433).

It is a self number, because there is not a number n which added to its sum of digits gives 91281432.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91281431) 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 35 ways as a sum of consecutive naturals, for example, 2122803 + ... + 2122845.

Almost surely, 2^91281432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91281432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135955260).

91281432 is an abundant number, since it is smaller than the sum of its proper divisors (180629088).

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

91281432 is a wasteful number, since it uses less digits than its factorization.

91281432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 76 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 91281432 is about 9554.1316716905. The cubic root of 91281432 is about 450.2573540263.

The spelling of 91281432 in words is "ninety-one million, two hundred eighty-one thousand, four hundred thirty-two".