218172190 has 8 divisors (see below), whose sum is σ = 392709960. Its totient is φ = 87268872.

The previous prime is 218172187. The next prime is 218172209. The reversal of 218172190 is 91271812.

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

It is a super-2 number, since 2×218172190² = 95198208978792200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10908600 + ... + 10908619.

It is an arithmetic number, because the mean of its divisors is an integer number (49088745).

Almost surely, 2^218172190 is an apocalyptic number.

218172190 is a deficient number, since it is larger than the sum of its proper divisors (174537770).

218172190 is a wasteful number, since it uses less digits than its factorization.

218172190 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21817226.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 218172190 is about 14770.6529984290. The cubic root of 218172190 is about 602.0045823281.

The spelling of 218172190 in words is "two hundred eighteen million, one hundred seventy-two thousand, one hundred ninety".