217302990 has 32 divisors (see below), whose sum is σ = 522321696. Its totient is φ = 57859200.

The previous prime is 217302977. The next prime is 217302991. The reversal of 217302990 is 99203712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217302991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15864 + ... + 26196.

It is an arithmetic number, because the mean of its divisors is an integer number (16322553).

Almost surely, 2^217302990 is an apocalyptic number.

217302990 is an abundant number, since it is smaller than the sum of its proper divisors (305018706).

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

217302990 is a wasteful number, since it uses less digits than its factorization.

217302990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11044.

The product of its (nonzero) digits is 6804, while the sum is 33.

The square root of 217302990 is about 14741.2004260169. The cubic root of 217302990 is about 601.2040543611.

The spelling of 217302990 in words is "two hundred seventeen million, three hundred two thousand, nine hundred ninety".