213131220 has 48 divisors (see below), whose sum is σ = 610653120. Its totient is φ = 55512576.

The previous prime is 213131209. The next prime is 213131249. The reversal of 213131220 is 22131312.

213131220 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 (15).

It is a self number, because there is not a number n which added to its sum of digits gives 213131220.

It is a congruent number.

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, 38725 + ... + 43884.

It is an arithmetic number, because the mean of its divisors is an integer number (12721940).

Almost surely, 2^213131220 is an apocalyptic number.

213131220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213131220 is an abundant number, since it is smaller than the sum of its proper divisors (397521900).

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

213131220 is a wasteful number, since it uses less digits than its factorization.

213131220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82664 (or 82662 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 213131220 is about 14599.0143502909. The cubic root of 213131220 is about 597.3318749909.

Adding to 213131220 its reverse (22131312), we get a palindrome (235262532).

The spelling of 213131220 in words is "two hundred thirteen million, one hundred thirty-one thousand, two hundred twenty".