181661222 has 8 divisors (see below), whose sum is σ = 284339376. Its totient is φ = 86881432.

The previous prime is 181661189. The next prime is 181661243. The reversal of 181661222 is 222166181.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1974533 + ... + 1974624.

It is an arithmetic number, because the mean of its divisors is an integer number (35542422).

Almost surely, 2^181661222 is an apocalyptic number.

181661222 is a deficient number, since it is larger than the sum of its proper divisors (102678154).

181661222 is a wasteful number, since it uses less digits than its factorization.

181661222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3949182.

The product of its digits is 2304, while the sum is 29.

The square root of 181661222 is about 13478.1757667720. The cubic root of 181661222 is about 566.3532674577.

The spelling of 181661222 in words is "one hundred eighty-one million, six hundred sixty-one thousand, two hundred twenty-two".