81253441 has 4 divisors (see below), whose sum is σ = 81972612. Its totient is φ = 80534272.

The previous prime is 81253439. The next prime is 81253451. The reversal of 81253441 is 14435218.

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 19395216 + 61858225 = 4404^2 + 7865^2 .

It is a cyclic number.

It is not a de Polignac number, because 81253441 - 2¹ = 81253439 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81253451) 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, 359416 + ... + 359641.

It is an arithmetic number, because the mean of its divisors is an integer number (20493153).

Almost surely, 2^81253441 is an apocalyptic number.

It is an amenable number.

81253441 is a deficient number, since it is larger than the sum of its proper divisors (719171).

81253441 is a wasteful number, since it uses less digits than its factorization.

81253441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719170.

The product of its digits is 3840, while the sum is 28.

The square root of 81253441 is about 9014.0690589766. The cubic root of 81253441 is about 433.1256668995.

Adding to 81253441 its reverse (14435218), we get a palindrome (95688659).

The spelling of 81253441 in words is "eighty-one million, two hundred fifty-three thousand, four hundred forty-one".