181358642 has 8 divisors (see below), whose sum is σ = 272171676. Its totient is φ = 90634752.

The previous prime is 181358581. The next prime is 181358647. The reversal of 181358642 is 246853181.

It can be written as a sum of positive squares in 2 ways, for example, as 170276401 + 11082241 = 13049^2 + 3329^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 181358596 and 181358605.

It is not an unprimeable number, because it can be changed into a prime (181358647) 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, 16943 + ... + 25490.

Almost surely, 2^181358642 is an apocalyptic number.

181358642 is a deficient number, since it is larger than the sum of its proper divisors (90813034).

181358642 is a wasteful number, since it uses less digits than its factorization.

181358642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44572.

The product of its digits is 46080, while the sum is 38.

The square root of 181358642 is about 13466.9462759751. The cubic root of 181358642 is about 566.0386481120.

The spelling of 181358642 in words is "one hundred eighty-one million, three hundred fifty-eight thousand, six hundred forty-two".