217949814 has 12 divisors (see below), whose sum is σ = 472224636. Its totient is φ = 72649932.

The previous prime is 217949803. The next prime is 217949821. The reversal of 217949814 is 418949712.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 217949814.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6054144 + ... + 6054179.

It is an arithmetic number, because the mean of its divisors is an integer number (39352053).

Almost surely, 2^217949814 is an apocalyptic number.

217949814 is an abundant number, since it is smaller than the sum of its proper divisors (254274822).

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

217949814 is a wasteful number, since it uses less digits than its factorization.

217949814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12108331 (or 12108328 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 217949814 is about 14763.1234500020. The cubic root of 217949814 is about 601.7999780651.

The spelling of 217949814 in words is "two hundred seventeen million, nine hundred forty-nine thousand, eight hundred fourteen".