213211404 has 72 divisors (see below), whose sum is σ = 622116768. Its totient is φ = 60307200.

The previous prime is 213211387. The next prime is 213211417. The reversal of 213211404 is 404112312.

Added to its reverse (404112312) it gives a square (617323716 = 24846²).

213211404 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21264 + ... + 29640.

Almost surely, 2^213211404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 213211404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311058384).

213211404 is an abundant number, since it is smaller than the sum of its proper divisors (408905364).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

213211404 is a wasteful number, since it uses less digits than its factorization.

213211404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8495 (or 8490 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 213211404 is about 14601.7603048400. The cubic root of 213211404 is about 597.4067747855.

Adding to 213211404 its reverse (404112312), we get a palindrome (617323716).

The spelling of 213211404 in words is "two hundred thirteen million, two hundred eleven thousand, four hundred four".