215623 has 4 divisors (see below), whose sum is σ = 216720. Its totient is φ = 214528.

The previous prime is 215617. The next prime is 215653. The reversal of 215623 is 326512.

It is a happy number.

215623 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 215623 - 2¹⁷ = 84551 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 215623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 163 + ... + 676.

It is an arithmetic number, because the mean of its divisors is an integer number (54180).

2²¹⁵⁶²³ is an apocalyptic number.

215623 is a deficient number, since it is larger than the sum of its proper divisors (1097).

215623 is an equidigital number, since it uses as much as digits as its factorization.

215623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1096.

The product of its digits is 360, while the sum is 19.

The square root of 215623 is about 464.3522369926. The cubic root of 215623 is about 59.9650722641.

Subtracting 215623 from its reverse (326512), we obtain a square (110889 = 333²).

It can be divided in two parts, 215 and 623, that added together give a palindrome (838).

The spelling of 215623 in words is "two hundred fifteen thousand, six hundred twenty-three".