81342994 has 32 divisors (see below), whose sum is σ = 133436160. Its totient is φ = 37041408.

The previous prime is 81342991. The next prime is 81343021. The reversal of 81342994 is 49924318.

It is not an unprimeable number, because it can be changed into a prime (81342991) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 173949 + ... + 174415.

It is an arithmetic number, because the mean of its divisors is an integer number (4169880).

Almost surely, 2^81342994 is an apocalyptic number.

81342994 is a deficient number, since it is larger than the sum of its proper divisors (52093166).

81342994 is a wasteful number, since it uses less digits than its factorization.

81342994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642.

The product of its digits is 62208, while the sum is 40.

The square root of 81342994 is about 9019.0350925141. The cubic root of 81342994 is about 433.2847307751.

The spelling of 81342994 in words is "eighty-one million, three hundred forty-two thousand, nine hundred ninety-four".