81325449 has 12 divisors (see below), whose sum is σ = 117564096. Its totient is φ = 54173592.

The previous prime is 81325417. The next prime is 81325451. The reversal of 81325449 is 94452318.

81325449 is a `hidden beast` number, since 81 + 32 + 544 + 9 = 666.

It is not a de Polignac number, because 81325449 - 2⁵ = 81325417 is a prime.

It is a super-2 number, since 2×81325449² = 13227657310103202, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81325469) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11652 + ... + 17274.

It is an arithmetic number, because the mean of its divisors is an integer number (9797008).

Almost surely, 2^81325449 is an apocalyptic number.

It is an amenable number.

81325449 is a deficient number, since it is larger than the sum of its proper divisors (36238647).

81325449 is a wasteful number, since it uses less digits than its factorization.

81325449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7236 (or 7233 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 81325449 is about 9018.0623750338. The cubic root of 81325449 is about 433.2535765771.

It can be divided in two parts, 813 and 25449, that added together give a palindrome (26262).

The spelling of 81325449 in words is "eighty-one million, three hundred twenty-five thousand, four hundred forty-nine".