81830159 has 4 divisors (see below), whose sum is σ = 85388016. Its totient is φ = 78272304.

The previous prime is 81830143. The next prime is 81830171. The reversal of 81830159 is 95103818.

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 81830159 - 2⁴ = 81830143 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 (81830179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1778894 + ... + 1778939.

It is an arithmetic number, because the mean of its divisors is an integer number (21347004).

Almost surely, 2^81830159 is an apocalyptic number.

81830159 is a deficient number, since it is larger than the sum of its proper divisors (3557857).

81830159 is a wasteful number, since it uses less digits than its factorization.

81830159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3557856.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 81830159 is about 9046.0023767408. The cubic root of 81830159 is about 434.1479936577.

The spelling of 81830159 in words is "eighty-one million, eight hundred thirty thousand, one hundred fifty-nine".