213404 has 12 divisors (see below), whose sum is σ = 385728. Its totient is φ = 103200.

The previous prime is 213397. The next prime is 213407. The reversal of 213404 is 404312.

Added to its reverse (404312) it gives a triangular number (617716 = T₁₁₁₁).

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 3 ways as a sum of consecutive naturals, for example, 737 + ... + 984.

It is an arithmetic number, because the mean of its divisors is an integer number (32144).

2²¹³⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

213404 is a deficient number, since it is larger than the sum of its proper divisors (172324).

213404 is a wasteful number, since it uses less digits than its factorization.

213404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1756 (or 1754 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 213404 is about 461.9567079284. The cubic root of 213404 is about 59.7586601827.

Adding to 213404 its reverse (404312), we get a palindrome (617716).

The spelling of 213404 in words is "two hundred thirteen thousand, four hundred four".