81698180290 has 16 divisors (see below), whose sum is σ = 147958915968. Its totient is φ = 32478785136.

The previous prime is 81698180273. The next prime is 81698180309. The reversal of 81698180290 is 9208189618.

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, 25059162 + ... + 25062421.

It is an arithmetic number, because the mean of its divisors is an integer number (9247432248).

Almost surely, 2^81698180290 is an apocalyptic number.

81698180290 is a deficient number, since it is larger than the sum of its proper divisors (66260735678).

81698180290 is a wasteful number, since it uses less digits than its factorization.

81698180290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50121753.

The product of its (nonzero) digits is 497664, while the sum is 52.

The spelling of 81698180290 in words is "eighty-one billion, six hundred ninety-eight million, one hundred eighty thousand, two hundred ninety".