81161285170 has 32 divisors (see below), whose sum is σ = 167325763968. Its totient is φ = 27765825408.

The previous prime is 81161285137. The next prime is 81161285201. The reversal of 81161285170 is 7158216118.

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, 1236552 + ... + 1300531.

It is an arithmetic number, because the mean of its divisors is an integer number (5228930124).

Almost surely, 2^81161285170 is an apocalyptic number.

81161285170 is an abundant number, since it is smaller than the sum of its proper divisors (86164478798).

81161285170 is a wasteful number, since it uses less digits than its factorization.

81161285170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2537554.

The product of its (nonzero) digits is 26880, while the sum is 40.

The spelling of 81161285170 in words is "eighty-one billion, one hundred sixty-one million, two hundred eighty-five thousand, one hundred seventy".