81158069 has 8 divisors (see below), whose sum is σ = 82481280. Its totient is φ = 79845696.

The previous prime is 81158039. The next prime is 81158081. The reversal of 81158069 is 96085118.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81158069 is a prime.

It is a super-2 number, since 2×81158069² = 13173264327617522, 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 (81158009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13124 + ... + 18290.

It is an arithmetic number, because the mean of its divisors is an integer number (10310160).

Almost surely, 2^81158069 is an apocalyptic number.

It is an amenable number.

81158069 is a deficient number, since it is larger than the sum of its proper divisors (1323211).

81158069 is a wasteful number, since it uses less digits than its factorization.

81158069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5419.

The product of its (nonzero) digits is 17280, while the sum is 38.

The square root of 81158069 is about 9008.7773310256. Note that the first 3 decimals coincide. The cubic root of 81158069 is about 432.9561387620.

The spelling of 81158069 in words is "eighty-one million, one hundred fifty-eight thousand, sixty-nine".