81981094 has 16 divisors (see below), whose sum is σ = 133746480. Its totient is φ = 37461600.

The previous prime is 81981079. The next prime is 81981101. The reversal of 81981094 is 49018918.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12984 + ... + 18235.

It is an arithmetic number, because the mean of its divisors is an integer number (8359155).

Almost surely, 2^81981094 is an apocalyptic number.

81981094 is a deficient number, since it is larger than the sum of its proper divisors (51765386).

81981094 is a wasteful number, since it uses less digits than its factorization.

81981094 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31335.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 81981094 is about 9054.3411687433. The cubic root of 81981094 is about 434.4147570808.

The spelling of 81981094 in words is "eighty-one million, nine hundred eighty-one thousand, ninety-four".