81858884 has 12 divisors (see below), whose sum is σ = 144672108. Its totient is φ = 40524000.

The previous prime is 81858883. The next prime is 81858899. The reversal of 81858884 is 48885818.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 80604484 + 1254400 = 8978^2 + 1120^2 .

It is not an unprimeable number, because it can be changed into a prime (81858883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100907 + ... + 101714.

It is an arithmetic number, because the mean of its divisors is an integer number (12056009).

Almost surely, 2^81858884 is an apocalyptic number.

It is an amenable number.

81858884 is a deficient number, since it is larger than the sum of its proper divisors (62813224).

81858884 is a wasteful number, since it uses less digits than its factorization.

81858884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202726 (or 202724 counting only the distinct ones).

The product of its digits is 655360, while the sum is 50.

The square root of 81858884 is about 9047.5899553417. The cubic root of 81858884 is about 434.1987876532.

The spelling of 81858884 in words is "eighty-one million, eight hundred fifty-eight thousand, eight hundred eighty-four".