223639 has 4 divisors (see below), whose sum is σ = 240856. Its totient is φ = 206424.

The previous prime is 223637. The next prime is 223667. The reversal of 223639 is 936322.

223639 = T₈₇ + T₈₈ + ... + T₁₂₅.

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

It is a cyclic number.

It is not a de Polignac number, because 223639 - 2¹ = 223637 is a prime.

It is a Duffinian number.

223639 is a lucky number.

It is a nialpdrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (223633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8589 + ... + 8614.

It is an arithmetic number, because the mean of its divisors is an integer number (60214).

2²²³⁶³⁹ is an apocalyptic number.

223639 is a deficient number, since it is larger than the sum of its proper divisors (17217).

223639 is a wasteful number, since it uses less digits than its factorization.

223639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17216.

The product of its digits is 1944, while the sum is 25.

The square root of 223639 is about 472.9048530096. The cubic root of 223639 is about 60.6991366389.

It can be divided in two parts, 2 and 23639, that multiplied together give a triangular number (47278 = T₃₀₇).

The spelling of 223639 in words is "two hundred twenty-three thousand, six hundred thirty-nine".