81306402859 has 32 divisors (see below), whose sum is σ = 96432629760. Its totient is φ = 67727404800.

The previous prime is 81306402851. The next prime is 81306402901. The reversal of 81306402859 is 95820460318.

It is not a de Polignac number, because 81306402859 - 2³ = 81306402851 is a prime.

It is a super-2 number, since 2×81306402859² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81306402851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21100177 + ... + 21104029.

It is an arithmetic number, because the mean of its divisors is an integer number (3013519680).

Almost surely, 2^81306402859 is an apocalyptic number.

81306402859 is a deficient number, since it is larger than the sum of its proper divisors (15126226901).

81306402859 is a wasteful number, since it uses less digits than its factorization.

81306402859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7171.

The product of its (nonzero) digits is 414720, while the sum is 46.

The spelling of 81306402859 in words is "eighty-one billion, three hundred six million, four hundred two thousand, eight hundred fifty-nine".