99981172 has 6 divisors (see below), whose sum is σ = 174967058. Its totient is φ = 49990584.

The previous prime is 99981163. The next prime is 99981179. The reversal of 99981172 is 27118999.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 76108176 + 23872996 = 8724^2 + 4886^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99981179) 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 as a sum of consecutive naturals, namely, 12497643 + ... + 12497650.

Almost surely, 2^99981172 is an apocalyptic number.

It is an amenable number.

99981172 is a deficient number, since it is larger than the sum of its proper divisors (74985886).

99981172 is a wasteful number, since it uses less digits than its factorization.

99981172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24995297 (or 24995295 counting only the distinct ones).

The product of its digits is 81648, while the sum is 46.

The square root of 99981172 is about 9999.0585556841. The cubic root of 99981172 is about 464.1297509213.

The spelling of 99981172 in words is "ninety-nine million, nine hundred eighty-one thousand, one hundred seventy-two".