81143804440 has 16 divisors (see below), whose sum is σ = 182573560080. Its totient is φ = 32457521760.

The previous prime is 81143804437. The next prime is 81143804447. The reversal of 81143804440 is 4440834118.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81143804440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81143804447) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1014297516 + ... + 1014297595.

It is an arithmetic number, because the mean of its divisors is an integer number (11410847505).

Almost surely, 2^81143804440 is an apocalyptic number.

It is an amenable number.

81143804440 is an abundant number, since it is smaller than the sum of its proper divisors (101429755640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81143804440 is a wasteful number, since it uses less digits than its factorization.

81143804440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2028595122 (or 2028595118 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 37.

The spelling of 81143804440 in words is "eighty-one billion, one hundred forty-three million, eight hundred four thousand, four hundred forty".