99981594 has 16 divisors (see below), whose sum is σ = 222181440. Its totient is φ = 33327180.

The previous prime is 99981593. The next prime is 99981599. The reversal of 99981594 is 49518999.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 1851511 = 99981594 / (9 + 9 + 9 + 8 + 1 + 5 + 9 + 4).

It is a self number, because there is not a number n which added to its sum of digits gives 99981594.

It is not an unprimeable number, because it can be changed into a prime (99981593) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 925702 + ... + 925809.

It is an arithmetic number, because the mean of its divisors is an integer number (13886340).

Almost surely, 2^99981594 is an apocalyptic number.

99981594 is an abundant number, since it is smaller than the sum of its proper divisors (122199846).

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

99981594 is a wasteful number, since it uses less digits than its factorization.

99981594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851522 (or 1851516 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 54.

The square root of 99981594 is about 9999.0796576485. The cubic root of 99981594 is about 464.1304039192.

The spelling of 99981594 in words is "ninety-nine million, nine hundred eighty-one thousand, five hundred ninety-four".