8142180581 has 4 divisors (see below), whose sum is σ = 8142384492. Its totient is φ = 8141976672.

The previous prime is 8142180559. The next prime is 8142180601. The reversal of 8142180581 is 1850812418.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4578687556 + 3563493025 = 67666^2 + 59695^2 .

It is a cyclic number.

It is not a de Polignac number, because 8142180581 - 2²⁶ = 8075071717 is a prime.

It is a super-2 number, since 2×8142180581² (a number of 21 digits) 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 (8142180511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20216 + ... + 129201.

It is an arithmetic number, because the mean of its divisors is an integer number (2035596123).

Almost surely, 2^8142180581 is an apocalyptic number.

It is an amenable number.

8142180581 is a deficient number, since it is larger than the sum of its proper divisors (203911).

8142180581 is a wasteful number, since it uses less digits than its factorization.

8142180581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203910.

The product of its (nonzero) digits is 20480, while the sum is 38.

The square root of 8142180581 is about 90234.0322771846. The cubic root of 8142180581 is about 2011.7788746211.

Adding to 8142180581 its reverse (1850812418), we get a palindrome (9992992999).

The spelling of 8142180581 in words is "eight billion, one hundred forty-two million, one hundred eighty thousand, five hundred eighty-one".