81560441 has 8 divisors (see below), whose sum is σ = 89336520. Its totient is φ = 74115328.

The previous prime is 81560393. The next prime is 81560443. The reversal of 81560441 is 14406518.

It can be written as a sum of positive squares in 4 ways, for example, as 33396841 + 48163600 = 5779^2 + 6940^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81560441 - 2²² = 77366137 is a prime.

It is a super-2 number, since 2×81560441² = 13304211072228962, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81560443) 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, 82226 + ... + 83211.

It is an arithmetic number, because the mean of its divisors is an integer number (11167065).

Almost surely, 2^81560441 is an apocalyptic number.

It is an amenable number.

81560441 is a deficient number, since it is larger than the sum of its proper divisors (7776079).

81560441 is a wasteful number, since it uses less digits than its factorization.

81560441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165483.

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 81560441 is about 9031.0819396128. The cubic root of 81560441 is about 433.6704744480.

Adding to 81560441 its reverse (14406518), we get a palindrome (95966959).

The spelling of 81560441 in words is "eighty-one million, five hundred sixty thousand, four hundred forty-one".