81436944 has 40 divisors (see below), whose sum is σ = 212923872. Its totient is φ = 26817280.

The previous prime is 81436937. The next prime is 81436961. The reversal of 81436944 is 44963418.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6237 + ... + 14204.

Almost surely, 2^81436944 is an apocalyptic number.

It is an amenable number.

81436944 is an abundant number, since it is smaller than the sum of its proper divisors (131486928).

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

81436944 is a wasteful number, since it uses less digits than its factorization.

81436944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20535 (or 20529 counting only the distinct ones).

The product of its digits is 82944, while the sum is 39.

The square root of 81436944 is about 9024.2420180312. The cubic root of 81436944 is about 433.4514791594.

The spelling of 81436944 in words is "eighty-one million, four hundred thirty-six thousand, nine hundred forty-four".