81325061 has 4 divisors (see below), whose sum is σ = 81344172. Its totient is φ = 81305952.

The previous prime is 81325043. The next prime is 81325063. The reversal of 81325061 is 16052318.

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 34880836 + 46444225 = 5906^2 + 6815^2 .

It is a cyclic number.

It is not a de Polignac number, because 81325061 - 2¹⁰ = 81324037 is a prime.

It is a super-2 number, since 2×81325061² = 13227531093307442, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81325061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81325063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41 + ... + 12753.

It is an arithmetic number, because the mean of its divisors is an integer number (20336043).

Almost surely, 2^81325061 is an apocalyptic number.

It is an amenable number.

81325061 is a deficient number, since it is larger than the sum of its proper divisors (19111).

81325061 is a wasteful number, since it uses less digits than its factorization.

81325061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19110.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 81325061 is about 9018.0408626264. The cubic root of 81325061 is about 433.2528875650.

Adding to 81325061 its reverse (16052318), we get a palindrome (97377379).

The spelling of 81325061 in words is "eighty-one million, three hundred twenty-five thousand, sixty-one".