217942293 has 16 divisors (see below), whose sum is σ = 306429120. Its totient is φ = 137402496.

The previous prime is 217942289. The next prime is 217942343. The reversal of 217942293 is 392249712.

It is not a de Polignac number, because 217942293 - 2² = 217942289 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217942693) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32071 + ... + 38267.

It is an arithmetic number, because the mean of its divisors is an integer number (19151820).

Almost surely, 2^217942293 is an apocalyptic number.

It is an amenable number.

217942293 is a deficient number, since it is larger than the sum of its proper divisors (88486827).

217942293 is a wasteful number, since it uses less digits than its factorization.

217942293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6836.

The product of its digits is 54432, while the sum is 39.

The square root of 217942293 is about 14762.8687252851. The cubic root of 217942293 is about 601.7930556922.

The spelling of 217942293 in words is "two hundred seventeen million, nine hundred forty-two thousand, two hundred ninety-three".