81338325 has 24 divisors (see below), whose sum is σ = 134741376. Its totient is φ = 43296000.

The previous prime is 81338317. The next prime is 81338329. The reversal of 81338325 is 52383318.

It is not a de Polignac number, because 81338325 - 2³ = 81338317 is a prime.

It is a super-2 number, since 2×81338325² = 13231846227611250, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81338329) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 65460 + ... + 66690.

It is an arithmetic number, because the mean of its divisors is an integer number (5614224).

Almost surely, 2^81338325 is an apocalyptic number.

It is an amenable number.

81338325 is a deficient number, since it is larger than the sum of its proper divisors (53403051).

81338325 is a wasteful number, since it uses less digits than its factorization.

81338325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2125 (or 2120 counting only the distinct ones).

The product of its digits is 17280, while the sum is 33.

The square root of 81338325 is about 9018.7762473631. The cubic root of 81338325 is about 433.2764405913.

The spelling of 81338325 in words is "eighty-one million, three hundred thirty-eight thousand, three hundred twenty-five".