81204974160 has 80 divisors (see below), whose sum is σ = 254563974720. Its totient is φ = 21411343360.

The previous prime is 81204974131. The next prime is 81204974233. The reversal of 81204974160 is 6147940218.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-5 number, since 5×81204974160⁵ (a number of 56 digits) contains 55555 as substring.

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, 1879506 + ... + 1922225.

It is an arithmetic number, because the mean of its divisors is an integer number (3182049684).

Almost surely, 2^81204974160 is an apocalyptic number.

81204974160 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81204974160 is an abundant number, since it is smaller than the sum of its proper divisors (173359000560).

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

81204974160 is a wasteful number, since it uses less digits than its factorization.

81204974160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3801836 (or 3801830 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 42.

The spelling of 81204974160 in words is "eighty-one billion, two hundred four million, nine hundred seventy-four thousand, one hundred sixty".