217280438 has 4 divisors (see below), whose sum is σ = 325920660. Its totient is φ = 108640218.

The previous prime is 217280431. The next prime is 217280473. The reversal of 217280438 is 834082712.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 217280398 and 217280407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217280431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54320108 + ... + 54320111.

It is an arithmetic number, because the mean of its divisors is an integer number (81480165).

Almost surely, 2^217280438 is an apocalyptic number.

217280438 is a deficient number, since it is larger than the sum of its proper divisors (108640222).

217280438 is a wasteful number, since it uses less digits than its factorization.

217280438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108640221.

The product of its (nonzero) digits is 21504, while the sum is 35.

The square root of 217280438 is about 14740.4354752497. The cubic root of 217280438 is about 601.1832557166.

The spelling of 217280438 in words is "two hundred seventeen million, two hundred eighty thousand, four hundred thirty-eight".