81899714 has 16 divisors (see below), whose sum is σ = 135528120. Its totient is φ = 36877440.

The previous prime is 81899663. The next prime is 81899717. The reversal of 81899714 is 41799818.

It can be written as a sum of positive squares in 4 ways, for example, as 62141689 + 19758025 = 7883^2 + 4445^2 .

It is not an unprimeable number, because it can be changed into a prime (81899717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37349 + ... + 39480.

Almost surely, 2^81899714 is an apocalyptic number.

81899714 is a deficient number, since it is larger than the sum of its proper divisors (53628406).

81899714 is a wasteful number, since it uses less digits than its factorization.

81899714 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76885.

The product of its digits is 145152, while the sum is 47.

The square root of 81899714 is about 9049.8460760391. The cubic root of 81899714 is about 434.2709662973.

The spelling of 81899714 in words is "eighty-one million, eight hundred ninety-nine thousand, seven hundred fourteen".