217391434 has 32 divisors (see below), whose sum is σ = 360383184. Its totient is φ = 97735680.

The previous prime is 217391431. The next prime is 217391441. The reversal of 217391434 is 434193712.

It can be written as a sum of positive squares in 8 ways, for example, as 22705225 + 194686209 = 4765^2 + 13953^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 217391434.

It is not an unprimeable number, because it can be changed into a prime (217391431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 178612 + ... + 179824.

Almost surely, 2^217391434 is an apocalyptic number.

217391434 is a deficient number, since it is larger than the sum of its proper divisors (142991750).

217391434 is a wasteful number, since it uses less digits than its factorization.

217391434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1402.

The product of its digits is 18144, while the sum is 34.

The square root of 217391434 is about 14744.2000122082. The cubic root of 217391434 is about 601.2856082000.

The spelling of 217391434 in words is "two hundred seventeen million, three hundred ninety-one thousand, four hundred thirty-four".