81450877844 has 24 divisors (see below), whose sum is σ = 163258240320. Its totient is φ = 34831129536.

The previous prime is 81450877843. The next prime is 81450877889. The reversal of 81450877844 is 44877805418.

It is a self number, because there is not a number n which added to its sum of digits gives 81450877844.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81450877843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3169874 + ... + 3195465.

It is an arithmetic number, because the mean of its divisors is an integer number (6802426680).

Almost surely, 2^81450877844 is an apocalyptic number.

It is an amenable number.

81450877844 is an abundant number, since it is smaller than the sum of its proper divisors (81807362476).

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

81450877844 is a wasteful number, since it uses less digits than its factorization.

81450877844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6365807 (or 6365805 counting only the distinct ones).

The product of its (nonzero) digits is 8028160, while the sum is 56.

The spelling of 81450877844 in words is "eighty-one billion, four hundred fifty million, eight hundred seventy-seven thousand, eight hundred forty-four".