31444220 has 48 divisors (see below), whose sum is σ = 72975168. Its totient is φ = 11320320.

The previous prime is 31444213. The next prime is 31444241. The reversal of 31444220 is 2244413.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31444192 and 31444201.

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, 5810 + ... + 9830.

It is an arithmetic number, because the mean of its divisors is an integer number (1520316).

Almost surely, 2^31444220 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 31444220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36487584).

31444220 is an abundant number, since it is smaller than the sum of its proper divisors (41530948).

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

31444220 is a wasteful number, since it uses less digits than its factorization.

31444220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4070 (or 4068 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 31444220 is about 5607.5146009618. The cubic root of 31444220 is about 315.6314535817.

Adding to 31444220 its reverse (2244413), we get a palindrome (33688633).

The spelling of 31444220 in words is "thirty-one million, four hundred forty-four thousand, two hundred twenty".