217940039 has 8 divisors (see below), whose sum is σ = 224172432. Its totient is φ = 211760640.

The previous prime is 217940033. The next prime is 217940053. The reversal of 217940039 is 930049712.

217940039 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 217940039 - 2⁸ = 217939783 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 217939990 and 217940008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217940033) 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, 4832 + ... + 21429.

It is an arithmetic number, because the mean of its divisors is an integer number (28021554).

Almost surely, 2^217940039 is an apocalyptic number.

217940039 is a deficient number, since it is larger than the sum of its proper divisors (6232393).

217940039 is a wasteful number, since it uses less digits than its factorization.

217940039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26497.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 217940039 is about 14762.7923849115. The cubic root of 217940039 is about 601.7909810662.

The spelling of 217940039 in words is "two hundred seventeen million, nine hundred forty thousand, thirty-nine".