221742173 has 8 divisors (see below), whose sum is σ = 222984576. Its totient is φ = 220504000.

The previous prime is 221742161. The next prime is 221742181. The reversal of 221742173 is 371247122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221742173 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 (221742133) 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, 172190 + ... + 173472.

It is an arithmetic number, because the mean of its divisors is an integer number (27873072).

Almost surely, 2^221742173 is an apocalyptic number.

It is an amenable number.

221742173 is a deficient number, since it is larger than the sum of its proper divisors (1242403).

221742173 is a wasteful number, since it uses less digits than its factorization.

221742173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2115.

The product of its digits is 4704, while the sum is 29.

The square root of 221742173 is about 14891.0098045767. The cubic root of 221742173 is about 605.2703961734.

Adding to 221742173 its reverse (371247122), we get a palindrome (592989295).

The spelling of 221742173 in words is "two hundred twenty-one million, seven hundred forty-two thousand, one hundred seventy-three".