81893412221039 has 24 divisors (see below), whose sum is σ = 86905584034560. Its totient is φ = 77156940096000.

The previous prime is 81893412220999. The next prime is 81893412221041. The reversal of 81893412221039 is 93012221439818.

It is not a de Polignac number, because 81893412221039 - 2⁴⁴ = 64301226176623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81893412221059) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 267997739 + ... + 268303139.

It is an arithmetic number, because the mean of its divisors is an integer number (3621066001440).

Almost surely, 2^{81893412221039} is an apocalyptic number.

81893412221039 is a deficient number, since it is larger than the sum of its proper divisors (5012171813521).

81893412221039 is a wasteful number, since it uses less digits than its factorization.

81893412221039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309519 (or 309500 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 53.

The spelling of 81893412221039 in words is "eighty-one trillion, eight hundred ninety-three billion, four hundred twelve million, two hundred twenty-one thousand, thirty-nine".