81394581452 has 24 divisors (see below), whose sum is σ = 150829801920. Its totient is φ = 38300683520.

The previous prime is 81394581383. The next prime is 81394581487. The reversal of 81394581452 is 25418549318.

It is a self number, because there is not a number n which added to its sum of digits gives 81394581452.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1237574 + ... + 1301682.

It is an arithmetic number, because the mean of its divisors is an integer number (6284575080).

Almost surely, 2^81394581452 is an apocalyptic number.

It is an amenable number.

81394581452 is a deficient number, since it is larger than the sum of its proper divisors (69435220468).

81394581452 is a wasteful number, since it uses less digits than its factorization.

81394581452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82801 (or 82799 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 50.

The spelling of 81394581452 in words is "eighty-one billion, three hundred ninety-four million, five hundred eighty-one thousand, four hundred fifty-two".