81089205 has 16 divisors (see below), whose sum is σ = 132192000. Its totient is φ = 42431168.

The previous prime is 81089189. The next prime is 81089213. The reversal of 81089205 is 50298018.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81089205 - 2⁴ = 81089189 is a prime.

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, 50205 + ... + 51794.

It is an arithmetic number, because the mean of its divisors is an integer number (8262000).

Almost surely, 2^81089205 is an apocalyptic number.

It is an amenable number.

81089205 is a deficient number, since it is larger than the sum of its proper divisors (51102795).

81089205 is a wasteful number, since it uses less digits than its factorization.

81089205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102060.

The product of its (nonzero) digits is 5760, while the sum is 33.

The square root of 81089205 is about 9004.9544696239. The cubic root of 81089205 is about 432.8336472310.

The spelling of 81089205 in words is "eighty-one million, eighty-nine thousand, two hundred five".