91693440 has 96 divisors (see below), whose sum is σ = 316648800. Its totient is φ = 24450048.

The previous prime is 91693439. The next prime is 91693451. The reversal of 91693440 is 4439619.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 91693395 and 91693404.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 2200 + ... + 13719.

It is an arithmetic number, because the mean of its divisors is an integer number (3298425).

Almost surely, 2^91693440 is an apocalyptic number.

91693440 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91693440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158324400).

91693440 is an abundant number, since it is smaller than the sum of its proper divisors (224955360).

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

91693440 is a wasteful number, since it uses less digits than its factorization.

91693440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15944 (or 15929 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 91693440 is about 9575.6691672175. The cubic root of 91693440 is about 450.9337647710.

The spelling of 91693440 in words is "ninety-one million, six hundred ninety-three thousand, four hundred forty".