81133469 has 4 divisors (see below), whose sum is σ = 85906044. Its totient is φ = 76360896.

The previous prime is 81133463. The next prime is 81133471. The reversal of 81133469 is 96433118.

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 25452025 + 55681444 = 5045^2 + 7462^2 .

It is a cyclic number.

It is not a de Polignac number, because 81133469 - 2⁴ = 81133453 is a prime.

It is a super-2 number, since 2×81133469² = 13165279583947922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81133463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2386262 + ... + 2386295.

It is an arithmetic number, because the mean of its divisors is an integer number (21476511).

Almost surely, 2^81133469 is an apocalyptic number.

It is an amenable number.

81133469 is a deficient number, since it is larger than the sum of its proper divisors (4772575).

81133469 is a wasteful number, since it uses less digits than its factorization.

81133469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4772574.

The product of its digits is 15552, while the sum is 35.

The square root of 81133469 is about 9007.4118924361. The cubic root of 81133469 is about 432.9123895803.

The spelling of 81133469 in words is "eighty-one million, one hundred thirty-three thousand, four hundred sixty-nine".