215638 has 8 divisors (see below), whose sum is σ = 326232. Its totient is φ = 106896.

The previous prime is 215617. The next prime is 215653. The reversal of 215638 is 836512.

It is a happy number.

215638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120 + ... + 667.

It is an arithmetic number, because the mean of its divisors is an integer number (40779).

2²¹⁵⁶³⁸ is an apocalyptic number.

215638 is a deficient number, since it is larger than the sum of its proper divisors (110594).

215638 is a wasteful number, since it uses less digits than its factorization.

215638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 926.

The product of its digits is 1440, while the sum is 25.

The square root of 215638 is about 464.3683882436. The cubic root of 215638 is about 59.9664627392.

The spelling of 215638 in words is "two hundred fifteen thousand, six hundred thirty-eight".