81441646 has 32 divisors (see below), whose sum is σ = 144482688. Its totient is φ = 33942240.

The previous prime is 81441637. The next prime is 81441667. The reversal of 81441646 is 64614418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45745 + ... + 47491.

It is an arithmetic number, because the mean of its divisors is an integer number (4515084).

Almost surely, 2^81441646 is an apocalyptic number.

81441646 is a deficient number, since it is larger than the sum of its proper divisors (63041042).

81441646 is a wasteful number, since it uses less digits than its factorization.

81441646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1936.

The product of its digits is 18432, while the sum is 34.

The square root of 81441646 is about 9024.5025347661. The cubic root of 81441646 is about 433.4598211949.

The spelling of 81441646 in words is "eighty-one million, four hundred forty-one thousand, six hundred forty-six".