81105650 has 24 divisors (see below), whose sum is σ = 151254084. Its totient is φ = 32356800.

The previous prime is 81105631. The next prime is 81105653. The reversal of 81105650 is 5650118.

It can be written as a sum of positive squares in 6 ways, for example, as 28121809 + 52983841 = 5303^2 + 7279^2 .

It is not an unprimeable number, because it can be changed into a prime (81105653) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19124 + ... + 22976.

Almost surely, 2^81105650 is an apocalyptic number.

81105650 is a deficient number, since it is larger than the sum of its proper divisors (70148434).

81105650 is a wasteful number, since it uses less digits than its factorization.

81105650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4286 (or 4281 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 81105650 is about 9005.8675317817. The cubic root of 81105650 is about 432.8629050021.

Adding to 81105650 its reverse (5650118), we get a palindrome (86755768).

The spelling of 81105650 in words is "eighty-one million, one hundred five thousand, six hundred fifty".