81955678 has 16 divisors (see below), whose sum is σ = 143763840. Its totient is φ = 34306776.

The previous prime is 81955663. The next prime is 81955697. The reversal of 81955678 is 87655918.

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, 67468 + ... + 68671.

It is an arithmetic number, because the mean of its divisors is an integer number (8985240).

Almost surely, 2^81955678 is an apocalyptic number.

81955678 is a deficient number, since it is larger than the sum of its proper divisors (61808162).

81955678 is a wasteful number, since it uses less digits than its factorization.

81955678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136191.

The product of its digits is 604800, while the sum is 49.

The square root of 81955678 is about 9052.9375343034. The cubic root of 81955678 is about 434.3698596290.

The spelling of 81955678 in words is "eighty-one million, nine hundred fifty-five thousand, six hundred seventy-eight".