81669418476 has 96 divisors (see below), whose sum is σ = 203283924480. Its totient is φ = 25472832000.

The previous prime is 81669418469. The next prime is 81669418477. The reversal of 81669418476 is 67481496618.

It is not an unprimeable number, because it can be changed into a prime (81669418477) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2135515 + ... + 2173421.

It is an arithmetic number, because the mean of its divisors is an integer number (2117540880).

Almost surely, 2^81669418476 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81669418476, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101641962240).

81669418476 is an abundant number, since it is smaller than the sum of its proper divisors (121614506004).

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

81669418476 is a wasteful number, since it uses less digits than its factorization.

81669418476 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38135 (or 38133 counting only the distinct ones).

The product of its digits is 13934592, while the sum is 60.

The spelling of 81669418476 in words is "eighty-one billion, six hundred sixty-nine million, four hundred eighteen thousand, four hundred seventy-six".