81443383863 has 16 divisors (see below), whose sum is σ = 112385095680. Its totient is φ = 52400277216.

The previous prime is 81443383793. The next prime is 81443383867. The reversal of 81443383863 is 36838334418.

It is a de Polignac number, because none of the positive numbers 2^k-81443383863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81443383867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5695 + ... + 403632.

It is an arithmetic number, because the mean of its divisors is an integer number (7024068480).

Almost surely, 2^81443383863 is an apocalyptic number.

81443383863 is a deficient number, since it is larger than the sum of its proper divisors (30941711817).

81443383863 is a wasteful number, since it uses less digits than its factorization.

81443383863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411646.

The product of its digits is 3981312, while the sum is 51.

The spelling of 81443383863 in words is "eighty-one billion, four hundred forty-three million, three hundred eighty-three thousand, eight hundred sixty-three".