81366229 has 8 divisors (see below), whose sum is σ = 93104640. Its totient is φ = 69656496.

The previous prime is 81366223. The next prime is 81366239. The reversal of 81366229 is 92266318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81366229 - 2²³ = 72977621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81366223) 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, 694 + ... + 12775.

It is an arithmetic number, because the mean of its divisors is an integer number (11638080).

Almost surely, 2^81366229 is an apocalyptic number.

It is an amenable number.

81366229 is a deficient number, since it is larger than the sum of its proper divisors (11738411).

81366229 is a wasteful number, since it uses less digits than its factorization.

81366229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14339.

The product of its digits is 31104, while the sum is 37.

The square root of 81366229 is about 9020.3231095122. The cubic root of 81366229 is about 433.3259816636.

It can be divided in two parts, 8136 and 6229, that added together give a triangular number (14365 = T₁₆₉).

The spelling of 81366229 in words is "eighty-one million, three hundred sixty-six thousand, two hundred twenty-nine".