81050866 has 16 divisors (see below), whose sum is σ = 138630744. Its totient is φ = 35207424.

The previous prime is 81050857. The next prime is 81050867. The reversal of 81050866 is 66805018.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 75429225 + 5621641 = 8685^2 + 2371^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (81050867) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91245 + ... + 92128.

Almost surely, 2^81050866 is an apocalyptic number.

81050866 is a deficient number, since it is larger than the sum of its proper divisors (57579878).

81050866 is a wasteful number, since it uses less digits than its factorization.

81050866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183405.

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 81050866 is about 9002.8254453810. The cubic root of 81050866 is about 432.7654218522.

The spelling of 81050866 in words is "eighty-one million, fifty thousand, eight hundred sixty-six".