217630730 has 8 divisors (see below), whose sum is σ = 391735332. Its totient is φ = 87052288.

The previous prime is 217630729. The next prime is 217630789. The reversal of 217630730 is 37036712.

It can be written as a sum of positive squares in 2 ways, for example, as 213832129 + 3798601 = 14623^2 + 1949^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 217630693 and 217630702.

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, 10881527 + ... + 10881546.

Almost surely, 2^217630730 is an apocalyptic number.

217630730 is a deficient number, since it is larger than the sum of its proper divisors (174104602).

217630730 is a wasteful number, since it uses less digits than its factorization.

217630730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21763080.

The product of its (nonzero) digits is 5292, while the sum is 29.

The square root of 217630730 is about 14752.3127000481. The cubic root of 217630730 is about 601.5061512025.

The spelling of 217630730 in words is "two hundred seventeen million, six hundred thirty thousand, seven hundred thirty".