218191000 has 32 divisors (see below), whose sum is σ = 510569280. Its totient is φ = 87276000.

The previous prime is 218190997. The next prime is 218191009. The reversal of 218191000 is 191812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218191009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108096 + ... + 110095.

It is an arithmetic number, because the mean of its divisors is an integer number (15955290).

Almost surely, 2^218191000 is an apocalyptic number.

218191000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218191000 is an abundant number, since it is smaller than the sum of its proper divisors (292378280).

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

218191000 is a wasteful number, since it uses less digits than its factorization.

218191000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218212 (or 218198 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 218191000 is about 14771.2897202648. The cubic root of 218191000 is about 602.0218827011.

The spelling of 218191000 in words is "two hundred eighteen million, one hundred ninety-one thousand".