217149439 has 8 divisors (see below), whose sum is σ = 233971472. Its totient is φ = 200344320.

The previous prime is 217149431. The next prime is 217149469. The reversal of 217149439 is 934941712.

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 217149439 - 2³ = 217149431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217149431) 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, 38479 + ... + 43759.

It is an arithmetic number, because the mean of its divisors is an integer number (29246434).

Almost surely, 2^217149439 is an apocalyptic number.

217149439 is a deficient number, since it is larger than the sum of its proper divisors (16822033).

217149439 is a wasteful number, since it uses less digits than its factorization.

217149439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8457.

The product of its digits is 54432, while the sum is 40.

The square root of 217149439 is about 14735.9912798563. The cubic root of 217149439 is about 601.0624130575.

The spelling of 217149439 in words is "two hundred seventeen million, one hundred forty-nine thousand, four hundred thirty-nine".