81143464689 has 96 divisors (see below), whose sum is σ = 143857459200. Its totient is φ = 44726774400.

The previous prime is 81143464679. The next prime is 81143464729. The reversal of 81143464689 is 98646434118.

81143464689 is a `hidden beast` number, since 8 + 114 + 3 + 464 + 68 + 9 = 666.

It is not a de Polignac number, because 81143464689 - 2⁵ = 81143464657 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81143464679) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17451637 + ... + 17456285.

It is an arithmetic number, because the mean of its divisors is an integer number (1498515200).

Almost surely, 2^81143464689 is an apocalyptic number.

It is an amenable number.

81143464689 is a deficient number, since it is larger than the sum of its proper divisors (62713994511).

81143464689 is a wasteful number, since it uses less digits than its factorization.

81143464689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5033 (or 5021 counting only the distinct ones).

The product of its digits is 3981312, while the sum is 54.

The spelling of 81143464689 in words is "eighty-one billion, one hundred forty-three million, four hundred sixty-four thousand, six hundred eighty-nine".