81406813340 has 48 divisors (see below), whose sum is σ = 173088492192. Its totient is φ = 32156553216.

The previous prime is 81406813339. The next prime is 81406813379. The reversal of 81406813340 is 4331860418.

It is a junction number, because it is equal to n+sod(n) for n = 81406813294 and 81406813303.

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, 4401392 + ... + 4419848.

It is an arithmetic number, because the mean of its divisors is an integer number (3606010254).

Almost surely, 2^81406813340 is an apocalyptic number.

It is an amenable number.

81406813340 is an abundant number, since it is smaller than the sum of its proper divisors (91681678852).

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

81406813340 is a wasteful number, since it uses less digits than its factorization.

81406813340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21206 (or 21204 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 38.

The spelling of 81406813340 in words is "eighty-one billion, four hundred six million, eight hundred thirteen thousand, three hundred forty".