81091465806402 has 48 divisors (see below), whose sum is σ = 187174671821280. Its totient is φ = 25284383404416.

The previous prime is 81091465806367. The next prime is 81091465806413. The reversal of 81091465806402 is 20460856419018.

81091465806402 is a `hidden beast` number, since 8 + 1 + 0 + 9 + 14 + 6 + 580 + 6 + 40 + 2 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 812848252 + ... + 812948007.

It is an arithmetic number, because the mean of its divisors is an integer number (3899472329610).

Almost surely, 2^{81091465806402} is an apocalyptic number.

81091465806402 is an abundant number, since it is smaller than the sum of its proper divisors (106083206014878).

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

81091465806402 is a wasteful number, since it uses less digits than its factorization.

81091465806402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1625796447 (or 1625796444 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 81091465806402 in words is "eighty-one trillion, ninety-one billion, four hundred sixty-five million, eight hundred six thousand, four hundred two".