217243457 has 8 divisors (see below), whose sum is σ = 221994432. Its totient is φ = 212539600.

The previous prime is 217243451. The next prime is 217243463. The reversal of 217243457 is 754342712.

It is an interprime number because it is at equal distance from previous prime (217243451) and next prime (217243463).

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

It is a cyclic number.

It is not a de Polignac number, because 217243457 - 2¹⁰ = 217242433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217243451) 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, 2378 + ... + 20979.

It is an arithmetic number, because the mean of its divisors is an integer number (27749304).

Almost surely, 2^217243457 is an apocalyptic number.

It is an amenable number.

217243457 is a deficient number, since it is larger than the sum of its proper divisors (4750975).

217243457 is a wasteful number, since it uses less digits than its factorization.

217243457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23559.

The product of its digits is 47040, while the sum is 35.

The square root of 217243457 is about 14739.1810152396. The cubic root of 217243457 is about 601.1491467718.

The spelling of 217243457 in words is "two hundred seventeen million, two hundred forty-three thousand, four hundred fifty-seven".