81394922 has 16 divisors (see below), whose sum is σ = 142938432. Its totient is φ = 34032480.

The previous prime is 81394921. The next prime is 81394939. The reversal of 81394922 is 22949318.

It is not an unprimeable number, because it can be changed into a prime (81394921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70328 + ... + 71475.

It is an arithmetic number, because the mean of its divisors is an integer number (8933652).

Almost surely, 2^81394922 is an apocalyptic number.

81394922 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

81394922 is a deficient number, since it is larger than the sum of its proper divisors (61543510).

81394922 is a wasteful number, since it uses less digits than its factorization.

81394922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141853.

The product of its digits is 31104, while the sum is 38.

The square root of 81394922 is about 9021.9134334131. The cubic root of 81394922 is about 433.3769117252.

The spelling of 81394922 in words is "eighty-one million, three hundred ninety-four thousand, nine hundred twenty-two".