181420638 has 24 divisors (see below), whose sum is σ = 422081352. Its totient is φ = 51834384.

The previous prime is 181420621. The next prime is 181420639. The reversal of 181420638 is 836024181.

181420638 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 181420599 and 181420608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181420639) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 308245 + ... + 308832.

It is an arithmetic number, because the mean of its divisors is an integer number (17586723).

Almost surely, 2^181420638 is an apocalyptic number.

181420638 is an abundant number, since it is smaller than the sum of its proper divisors (240660714).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

181420638 is a wasteful number, since it uses less digits than its factorization.

181420638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617096 (or 617089 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 181420638 is about 13469.2478631882. The cubic root of 181420638 is about 566.1031393575.

The spelling of 181420638 in words is "one hundred eighty-one million, four hundred twenty thousand, six hundred thirty-eight".