81859562 has 16 divisors (see below), whose sum is σ = 129487200. Its totient is φ = 38705040.

The previous prime is 81859549. The next prime is 81859579. The reversal of 81859562 is 26595818.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23489 + ... + 26747.

It is an arithmetic number, because the mean of its divisors is an integer number (8092950).

Almost surely, 2^81859562 is an apocalyptic number.

81859562 is a deficient number, since it is larger than the sum of its proper divisors (47627638).

81859562 is a wasteful number, since it uses less digits than its factorization.

81859562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3941.

The product of its digits is 172800, while the sum is 44.

The square root of 81859562 is about 9047.6274238056. The cubic root of 81859562 is about 434.1999864071.

The spelling of 81859562 in words is "eighty-one million, eight hundred fifty-nine thousand, five hundred sixty-two".