81131874280 has 32 divisors (see below), whose sum is σ = 183666650400. Its totient is φ = 32253650496.

The previous prime is 81131874269. The next prime is 81131874287. The reversal of 81131874280 is 8247813118.

It is not an unprimeable number, because it can be changed into a prime (81131874287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6215250 + ... + 6228289.

It is an arithmetic number, because the mean of its divisors is an integer number (5739582825).

Almost surely, 2^81131874280 is an apocalyptic number.

It is an amenable number.

81131874280 is an abundant number, since it is smaller than the sum of its proper divisors (102534776120).

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

81131874280 is a wasteful number, since it uses less digits than its factorization.

81131874280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12443713 (or 12443709 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 43.

The spelling of 81131874280 in words is "eighty-one billion, one hundred thirty-one million, eight hundred seventy-four thousand, two hundred eighty".