213205556 has 12 divisors (see below), whose sum is σ = 375044292. Its totient is φ = 106050048.

The previous prime is 213205547. The next prime is 213205589. The reversal of 213205556 is 655502312.

213205556 = T₃₂₃ + T₃₂₄ + ... + T₁₀₉₄.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 86192656 + 127012900 = 9284^2 + 11270^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137315 + ... + 138858.

It is an arithmetic number, because the mean of its divisors is an integer number (31253691).

Almost surely, 2^213205556 is an apocalyptic number.

It is an amenable number.

213205556 is a deficient number, since it is larger than the sum of its proper divisors (161838736).

213205556 is a wasteful number, since it uses less digits than its factorization.

213205556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276370 (or 276368 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 29.

The square root of 213205556 is about 14601.5600536381. The cubic root of 213205556 is about 597.4013128094.

Adding to 213205556 its reverse (655502312), we get a palindrome (868707868).

The spelling of 213205556 in words is "two hundred thirteen million, two hundred five thousand, five hundred fifty-six".