213216556 has 48 divisors (see below), whose sum is σ = 451010560. Its totient is φ = 86158080.

The previous prime is 213216541. The next prime is 213216569. The reversal of 213216556 is 655612312.

It is a super-2 number, since 2×213216556² = 90922599505002272, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127381 + ... + 129043.

Almost surely, 2^213216556 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 213216556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225505280).

213216556 is an abundant number, since it is smaller than the sum of its proper divisors (237794004).

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

213216556 is a wasteful number, since it uses less digits than its factorization.

213216556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1934 (or 1932 counting only the distinct ones).

The product of its digits is 10800, while the sum is 31.

The square root of 213216556 is about 14601.9367208600. The cubic root of 213216556 is about 597.4115866215.

Adding to 213216556 its reverse (655612312), we get a palindrome (868828868).

The spelling of 213216556 in words is "two hundred thirteen million, two hundred sixteen thousand, five hundred fifty-six".