81407166 has 32 divisors (see below), whose sum is σ = 170346240. Its totient is φ = 25886784.

The previous prime is 81407159. The next prime is 81407173. The reversal of 81407166 is 66170418.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81407159) and next prime (81407173).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84946 + ... + 85898.

It is an arithmetic number, because the mean of its divisors is an integer number (5323320).

Almost surely, 2^81407166 is an apocalyptic number.

81407166 is an abundant number, since it is smaller than the sum of its proper divisors (88939074).

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

81407166 is a wasteful number, since it uses less digits than its factorization.

81407166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1600.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 81407166 is about 9022.5919779185. The cubic root of 81407166 is about 433.3986411760.

The spelling of 81407166 in words is "eighty-one million, four hundred seven thousand, one hundred sixty-six".