213218404 has 45 divisors (see below), whose sum is σ = 438236057. Its totient is φ = 90766032.

The previous prime is 213218371. The next prime is 213218413. The reversal of 213218404 is 404812312.

The square root of 213218404 is 14602.

It is a perfect power (a square), and thus also a powerful number.

213218404 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 24980004 + 188238400 = 4998^2 + 13720^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 1430922 + ... + 1431070.

Almost surely, 2^213218404 is an apocalyptic number.

213218404 is the 14602-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 213218404

213218404 is an abundant number, since it is smaller than the sum of its proper divisors (225017653).

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

213218404 is an frugal number, since it uses more digits than its factorization.

213218404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The cubic root of 213218404 is about 597.4133125872.

Multiplying 213218404 by its sum of digits (25), we get a square (5330460100 = 73010²).

The spelling of 213218404 in words is "two hundred thirteen million, two hundred eighteen thousand, four hundred four".