213405 has 16 divisors (see below), whose sum is σ = 350784. Its totient is φ = 110720.

The previous prime is 213397. The next prime is 213407. The reversal of 213405 is 504312.

213405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 213405 - 2³ = 213397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213407) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 442 + ... + 788.

It is an arithmetic number, because the mean of its divisors is an integer number (21924).

2²¹³⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

213405 is a deficient number, since it is larger than the sum of its proper divisors (137379).

213405 is a wasteful number, since it uses less digits than its factorization.

213405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 213405 is about 461.9577902796. The cubic root of 213405 is about 59.7587535246.

Adding to 213405 its reverse (504312), we get a palindrome (717717).

The spelling of 213405 in words is "two hundred thirteen thousand, four hundred five".