99581040 has 120 divisors (see below), whose sum is σ = 360185280. Its totient is φ = 24509952.

The previous prime is 99581039. The next prime is 99581047. The reversal of 99581040 is 4018599.

It is a tau number, because it is divible by the number of its divisors (120).

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 = 99580986 and 99581004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99581047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4041 + ... + 14679.

It is an arithmetic number, because the mean of its divisors is an integer number (3001544).

Almost surely, 2^99581040 is an apocalyptic number.

99581040 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 99581040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180092640).

99581040 is an abundant number, since it is smaller than the sum of its proper divisors (260604240).

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

99581040 is a wasteful number, since it uses less digits than its factorization.

99581040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10671 (or 10662 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 99581040 is about 9979.0300129822. The cubic root of 99581040 is about 463.5097626442.

The spelling of 99581040 in words is "ninety-nine million, five hundred eighty-one thousand, forty".