81229369 has 8 divisors (see below), whose sum is σ = 88912712. Its totient is φ = 73751040.

The previous prime is 81229333. The next prime is 81229381. The reversal of 81229369 is 96392218.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 13225 + 81216144 = 115^2 + 9012^2 .

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 81229369 - 2¹³ = 81221177 is a prime.

It is a super-2 number, since 2×81229369² = 13196420776276322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81229069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50424 + ... + 52009.

It is an arithmetic number, because the mean of its divisors is an integer number (11114089).

Almost surely, 2^81229369 is an apocalyptic number.

It is an amenable number.

81229369 is a deficient number, since it is larger than the sum of its proper divisors (7683343).

81229369 is a wasteful number, since it uses less digits than its factorization.

81229369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102507.

The product of its digits is 46656, while the sum is 40.

The square root of 81229369 is about 9012.7337140293. The cubic root of 81229369 is about 433.0828903282.

The spelling of 81229369 in words is "eighty-one million, two hundred twenty-nine thousand, three hundred sixty-nine".