81010445 has 4 divisors (see below), whose sum is σ = 97212540. Its totient is φ = 64808352.

The previous prime is 81010441. The next prime is 81010453. The reversal of 81010445 is 54401018.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56220004 + 24790441 = 7498^2 + 4979^2 .

It is a cyclic number.

It is not a de Polignac number, because 81010445 - 2² = 81010441 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81010445.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81010441) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8101040 + ... + 8101049.

It is an arithmetic number, because the mean of its divisors is an integer number (24303135).

Almost surely, 2^81010445 is an apocalyptic number.

It is an amenable number.

81010445 is a deficient number, since it is larger than the sum of its proper divisors (16202095).

81010445 is a wasteful number, since it uses less digits than its factorization.

81010445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16202094.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 81010445 is about 9000.5802590722. The cubic root of 81010445 is about 432.6934681901.

The spelling of 81010445 in words is "eighty-one million, ten thousand, four hundred forty-five".