81269359 has 4 divisors (see below), whose sum is σ = 81862704. Its totient is φ = 80676016.

The previous prime is 81269351. The next prime is 81269407. The reversal of 81269359 is 95396218.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81269359 - 2³ = 81269351 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 (81269351) 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 3 ways as a sum of consecutive naturals, for example, 296467 + ... + 296740.

It is an arithmetic number, because the mean of its divisors is an integer number (20465676).

Almost surely, 2^81269359 is an apocalyptic number.

81269359 is a deficient number, since it is larger than the sum of its proper divisors (593345).

81269359 is a wasteful number, since it uses less digits than its factorization.

81269359 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593344.

The product of its digits is 116640, while the sum is 43.

The square root of 81269359 is about 9014.9519688127. The cubic root of 81269359 is about 433.1539489600.

The spelling of 81269359 in words is "eighty-one million, two hundred sixty-nine thousand, three hundred fifty-nine".