31105224 has 72 divisors (see below), whose sum is σ = 86684130. Its totient is φ = 10076160.

The previous prime is 31105201. The next prime is 31105237. The reversal of 31105224 is 42250113.

It can be written as a sum of positive squares in 3 ways, for example, as 20412324 + 10692900 = 4518^2 + 3270^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 31105197 and 31105206.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 120904 + ... + 121160.

Almost surely, 2^31105224 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 31105224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43342065).

31105224 is an abundant number, since it is smaller than the sum of its proper divisors (55578906).

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

31105224 is a wasteful number, since it uses less digits than its factorization.

31105224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 31105224 is about 5577.2057519873. The cubic root of 31105224 is about 314.4930924920.

Adding to 31105224 its reverse (42250113), we get a palindrome (73355337).

It can be divided in two parts, 31105 and 224, that added together give a square (31329 = 177²).

The spelling of 31105224 in words is "thirty-one million, one hundred five thousand, two hundred twenty-four".