131213220 has 48 divisors (see below), whose sum is σ = 370063680. Its totient is φ = 34736256.

The previous prime is 131213177. The next prime is 131213249. The reversal of 131213220 is 22312131.

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 131213220.

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, 474 + ... + 16206.

It is an arithmetic number, because the mean of its divisors is an integer number (7709660).

Almost surely, 2^131213220 is an apocalyptic number.

131213220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 131213220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185031840).

131213220 is an abundant number, since it is smaller than the sum of its proper divisors (238850460).

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

131213220 is a wasteful number, since it uses less digits than its factorization.

131213220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15884 (or 15882 counting only the distinct ones).

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

The square root of 131213220 is about 11454.8339141168. The cubic root of 131213220 is about 508.1507034227.

Adding to 131213220 its reverse (22312131), we get a palindrome (153525351).

The spelling of 131213220 in words is "one hundred thirty-one million, two hundred thirteen thousand, two hundred twenty".