81899330 has 32 divisors (see below), whose sum is σ = 149878080. Its totient is φ = 32218560.

The previous prime is 81899327. The next prime is 81899341. The reversal of 81899330 is 3399818.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 247265 + ... + 247595.

It is an arithmetic number, because the mean of its divisors is an integer number (4683690).

Almost surely, 2^81899330 is an apocalyptic number.

81899330 is a deficient number, since it is larger than the sum of its proper divisors (67978750).

81899330 is a wasteful number, since it uses less digits than its factorization.

81899330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 81899330 is about 9049.8248601838. The cubic root of 81899330 is about 434.2702875798.

The spelling of 81899330 in words is "eighty-one million, eight hundred ninety-nine thousand, three hundred thirty".