81812366 has 8 divisors (see below), whose sum is σ = 129177480. Its totient is φ = 38753208.

The previous prime is 81812363. The next prime is 81812387. The reversal of 81812366 is 66321818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81812363) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1076441 + ... + 1076516.

It is an arithmetic number, because the mean of its divisors is an integer number (16147185).

Almost surely, 2^81812366 is an apocalyptic number.

81812366 is a deficient number, since it is larger than the sum of its proper divisors (47365114).

81812366 is a wasteful number, since it uses less digits than its factorization.

81812366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2152978.

The product of its digits is 13824, while the sum is 35.

The square root of 81812366 is about 9045.0188501738. The cubic root of 81812366 is about 434.1165245951.

The spelling of 81812366 in words is "eighty-one million, eight hundred twelve thousand, three hundred sixty-six".