81819367 has 6 divisors (see below), whose sum is σ = 95177688. Its totient is φ = 70130844.

The previous prime is 81819359. The next prime is 81819379. The reversal of 81819367 is 76391818.

It is not a de Polignac number, because 81819367 - 2³ = 81819359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81819307) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 834843 + ... + 834940.

It is an arithmetic number, because the mean of its divisors is an integer number (15862948).

Almost surely, 2^81819367 is an apocalyptic number.

81819367 is a deficient number, since it is larger than the sum of its proper divisors (13358321).

81819367 is a wasteful number, since it uses less digits than its factorization.

81819367 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669797 (or 1669790 counting only the distinct ones).

The product of its digits is 72576, while the sum is 43.

The square root of 81819367 is about 9045.4058504856. The cubic root of 81819367 is about 434.1289072508.

The spelling of 81819367 in words is "eighty-one million, eight hundred nineteen thousand, three hundred sixty-seven".