213815 has 16 divisors (see below), whose sum is σ = 302400. Its totient is φ = 142080.

The previous prime is 213799. The next prime is 213821. The reversal of 213815 is 518312.

It is not a de Polignac number, because 213815 - 2⁴ = 213799 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1361 + ... + 1509.

It is an arithmetic number, because the mean of its divisors is an integer number (18900).

2²¹³⁸¹⁵ is an apocalyptic number.

213815 is a deficient number, since it is larger than the sum of its proper divisors (88585).

213815 is a wasteful number, since it uses less digits than its factorization.

213815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202.

The product of its digits is 240, while the sum is 20.

The square root of 213815 is about 462.4013408285. The cubic root of 213815 is about 59.7969991373.

The spelling of 213815 in words is "two hundred thirteen thousand, eight hundred fifteen".