99981499 has 4 divisors (see below), whose sum is σ = 100143640. Its totient is φ = 99819360.

The previous prime is 99981491. The next prime is 99981509. The reversal of 99981499 is 99418999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99418999 = 103 ⋅965233.

It is a cyclic number.

It is not a de Polignac number, because 99981499 - 2³ = 99981491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99981491) 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 3 ways as a sum of consecutive naturals, for example, 80142 + ... + 81379.

It is an arithmetic number, because the mean of its divisors is an integer number (25035910).

Almost surely, 2^99981499 is an apocalyptic number.

99981499 is a deficient number, since it is larger than the sum of its proper divisors (162141).

99981499 is a wasteful number, since it uses less digits than its factorization.

99981499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162140.

The product of its digits is 1889568, while the sum is 58.

The square root of 99981499 is about 9999.0749072102. The cubic root of 99981499 is about 464.1302569175.

Subtracting from 99981499 its reverse (99418999), we obtain a square (562500 = 750²).

The spelling of 99981499 in words is "ninety-nine million, nine hundred eighty-one thousand, four hundred ninety-nine".