81839416 has 32 divisors (see below), whose sum is σ = 156492000. Its totient is φ = 40116736.

The previous prime is 81839399. The next prime is 81839423. The reversal of 81839416 is 61493818.

It is a super-2 number, since 2×81839416² = 13395380022442112, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 97125 + ... + 97963.

It is an arithmetic number, because the mean of its divisors is an integer number (4890375).

Almost surely, 2^81839416 is an apocalyptic number.

It is an amenable number.

81839416 is a deficient number, since it is larger than the sum of its proper divisors (74652584).

81839416 is a wasteful number, since it uses less digits than its factorization.

81839416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071 (or 1067 counting only the distinct ones).

The product of its digits is 41472, while the sum is 40.

The square root of 81839416 is about 9046.5140247501. The cubic root of 81839416 is about 434.1643639728.

The spelling of 81839416 in words is "eighty-one million, eight hundred thirty-nine thousand, four hundred sixteen".