81955394 has 16 divisors (see below), whose sum is σ = 128478528. Its totient is φ = 39134832.

The previous prime is 81955361. The next prime is 81955403. The reversal of 81955394 is 49355918.

It is a happy 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, 44969 + ... + 46755.

It is an arithmetic number, because the mean of its divisors is an integer number (8029908).

Almost surely, 2^81955394 is an apocalyptic number.

81955394 is a deficient number, since it is larger than the sum of its proper divisors (46523134).

81955394 is a wasteful number, since it uses less digits than its factorization.

81955394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2809.

The product of its digits is 194400, while the sum is 44.

The square root of 81955394 is about 9052.9218487735. The cubic root of 81955394 is about 434.3693578896.

The spelling of 81955394 in words is "eighty-one million, nine hundred fifty-five thousand, three hundred ninety-four".