217723130 has 8 divisors (see below), whose sum is σ = 391901652. Its totient is φ = 87089248.

The previous prime is 217723127. The next prime is 217723141. The reversal of 217723130 is 31327712.

It can be written as a sum of positive squares in 2 ways, for example, as 216943441 + 779689 = 14729^2 + 883^2 .

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

It is a super-2 number, since 2×217723130² = 94806722673993800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 217723130.

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, 10886147 + ... + 10886166.

Almost surely, 2^217723130 is an apocalyptic number.

217723130 is a deficient number, since it is larger than the sum of its proper divisors (174178522).

217723130 is a wasteful number, since it uses less digits than its factorization.

217723130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21772320.

The product of its (nonzero) digits is 1764, while the sum is 26.

The square root of 217723130 is about 14755.4440800675. Note that the first 3 decimals coincide. The cubic root of 217723130 is about 601.5912667932.

The spelling of 217723130 in words is "two hundred seventeen million, seven hundred twenty-three thousand, one hundred thirty".