81436884 has 12 divisors (see below), whose sum is σ = 190019424. Its totient is φ = 27145624.

The previous prime is 81436879. The next prime is 81436897. The reversal of 81436884 is 48863418.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3393192 + ... + 3393215.

It is an arithmetic number, because the mean of its divisors is an integer number (15834952).

Almost surely, 2^81436884 is an apocalyptic number.

It is an amenable number.

81436884 is an abundant number, since it is smaller than the sum of its proper divisors (108582540).

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

81436884 is a wasteful number, since it uses less digits than its factorization.

81436884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6786414 (or 6786412 counting only the distinct ones).

The product of its digits is 147456, while the sum is 42.

The square root of 81436884 is about 9024.2386936517. The cubic root of 81436884 is about 433.4513727085.

The spelling of 81436884 in words is "eighty-one million, four hundred thirty-six thousand, eight hundred eighty-four".