99437981 has 16 divisors (see below), whose sum is σ = 108961200. Its totient is φ = 90362880.

The previous prime is 99437977. The next prime is 99438019. The reversal of 99437981 is 18973499.

It can be written as a sum of positive squares in 8 ways, for example, as 5522500 + 93915481 = 2350^2 + 9691^2 .

It is not a de Polignac number, because 99437981 - 2² = 99437977 is a prime.

It is a super-2 number, since 2×99437981² = 19775824130712722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99437081) 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 15 ways as a sum of consecutive naturals, for example, 93191 + ... + 94251.

It is an arithmetic number, because the mean of its divisors is an integer number (6810075).

Almost surely, 2^99437981 is an apocalyptic number.

It is an amenable number.

99437981 is a deficient number, since it is larger than the sum of its proper divisors (9523219).

99437981 is a wasteful number, since it uses less digits than its factorization.

99437981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1264.

The product of its digits is 489888, while the sum is 50.

The square root of 99437981 is about 9971.8594554877. The cubic root of 99437981 is about 463.2876955319.

The spelling of 99437981 in words is "ninety-nine million, four hundred thirty-seven thousand, nine hundred eighty-one".