81166000 has 40 divisors (see below), whose sum is σ = 196264224. Its totient is φ = 32465600.

The previous prime is 81165991. The next prime is 81166031. The reversal of 81166000 is 66118.

It is a tau number, because it is divible by the number of its divisors (40).

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, 18292 + ... + 22291.

Almost surely, 2^81166000 is an apocalyptic number.

81166000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81166000 is an abundant number, since it is smaller than the sum of its proper divisors (115098224).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81166000 is a wasteful number, since it uses less digits than its factorization.

81166000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40606 (or 40590 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 81166000 is about 9009.2175020920. The cubic root of 81166000 is about 432.9702415425.

The spelling of 81166000 in words is "eighty-one million, one hundred sixty-six thousand".