181383638 has 4 divisors (see below), whose sum is σ = 272075460. Its totient is φ = 90691818.

The previous prime is 181383623. The next prime is 181383647. The reversal of 181383638 is 836383181.

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

It is a junction number, because it is equal to n+sod(n) for n = 181383595 and 181383604.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 45345908 + ... + 45345911.

It is an arithmetic number, because the mean of its divisors is an integer number (68018865).

Almost surely, 2^181383638 is an apocalyptic number.

181383638 is a deficient number, since it is larger than the sum of its proper divisors (90691822).

181383638 is an equidigital number, since it uses as much as digits as its factorization.

181383638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90691821.

The product of its digits is 82944, while the sum is 41.

The square root of 181383638 is about 13467.8742940376. The cubic root of 181383638 is about 566.0646519313.

The spelling of 181383638 in words is "one hundred eighty-one million, three hundred eighty-three thousand, six hundred thirty-eight".