81494159 has 8 divisors (see below), whose sum is σ = 83629392. Its totient is φ = 79369920.

The previous prime is 81494137. The next prime is 81494201. The reversal of 81494159 is 95149418.

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-81494159 is a prime.

It is a super-2 number, since 2×81494159² = 13282595902234562, 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 (81494659) 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 7 ways as a sum of consecutive naturals, for example, 13499 + ... + 18579.

It is an arithmetic number, because the mean of its divisors is an integer number (10453674).

Almost surely, 2^81494159 is an apocalyptic number.

81494159 is a deficient number, since it is larger than the sum of its proper divisors (2135233).

81494159 is a wasteful number, since it uses less digits than its factorization.

81494159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5497.

The product of its digits is 51840, while the sum is 41.

The square root of 81494159 is about 9027.4115337676. The cubic root of 81494159 is about 433.5529651253.

The spelling of 81494159 in words is "eighty-one million, four hundred ninety-four thousand, one hundred fifty-nine".