81445269 has 8 divisors (see below), whose sum is σ = 108788832. Its totient is φ = 54199280.

The previous prime is 81445261. The next prime is 81445279. The reversal of 81445269 is 96254418.

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 81445269 - 2³ = 81445261 is a prime.

It is a super-2 number, since 2×81445269² = 13266663684964722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81445261) 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 7 ways as a sum of consecutive naturals, for example, 22422 + ... + 25799.

It is an arithmetic number, because the mean of its divisors is an integer number (13598604).

Almost surely, 2^81445269 is an apocalyptic number.

It is an amenable number.

81445269 is a deficient number, since it is larger than the sum of its proper divisors (27343563).

81445269 is a wasteful number, since it uses less digits than its factorization.

81445269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48787.

The product of its digits is 69120, while the sum is 39.

The square root of 81445269 is about 9024.7032638198. The cubic root of 81445269 is about 433.4662487076.

The spelling of 81445269 in words is "eighty-one million, four hundred forty-five thousand, two hundred sixty-nine".