81085147 has 16 divisors (see below), whose sum is σ = 95622912. Its totient is φ = 67785120.

The previous prime is 81085139. The next prime is 81085163. The reversal of 81085147 is 74158018.

It is not a de Polignac number, because 81085147 - 2³ = 81085139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81085127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42978 + ... + 44824.

It is an arithmetic number, because the mean of its divisors is an integer number (5976432).

Almost surely, 2^81085147 is an apocalyptic number.

81085147 is a deficient number, since it is larger than the sum of its proper divisors (14537765).

81085147 is a wasteful number, since it uses less digits than its factorization.

81085147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2178.

The product of its (nonzero) digits is 8960, while the sum is 34.

The square root of 81085147 is about 9004.7291463986. The cubic root of 81085147 is about 432.8264269183.

The spelling of 81085147 in words is "eighty-one million, eighty-five thousand, one hundred forty-seven".