8631220 has 48 divisors (see below), whose sum is σ = 19792080. Its totient is φ = 3142656.

The previous prime is 8631199. The next prime is 8631229. The reversal of 8631220 is 221368.

8631220 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 8 ways, for example, as 1373584 + 7257636 = 1172^2 + 2694^2 .

It is a junction number, because it is equal to n+sod(n) for n = 8631191 and 8631200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8631229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22954 + ... + 23326.

It is an arithmetic number, because the mean of its divisors is an integer number (412335).

Almost surely, 2^8631220 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 8631220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9896040).

8631220 is an abundant number, since it is smaller than the sum of its proper divisors (11160860).

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

8631220 is a wasteful number, since it uses less digits than its factorization.

8631220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484 (or 482 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 8631220 is about 2937.8938033904. The cubic root of 8631220 is about 205.1275826877.

Adding to 8631220 its reverse (221368), we get a palindrome (8852588).

The spelling of 8631220 in words is "eight million, six hundred thirty-one thousand, two hundred twenty".