31221044 has 24 divisors (see below), whose sum is σ = 59419080. Its totient is φ = 14294016.

The previous prime is 31221041. The next prime is 31221103. The reversal of 31221044 is 44012213.

It can be written as a sum of positive squares in 4 ways, for example, as 6100900 + 25120144 = 2470^2 + 5012^2 .

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31221041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3689 + ... + 8720.

It is an arithmetic number, because the mean of its divisors is an integer number (2475795).

Almost surely, 2^31221044 is an apocalyptic number.

31221044 is a gapful number since it is divisible by the number (34) formed by its first and last digit.

It is an amenable number.

31221044 is a deficient number, since it is larger than the sum of its proper divisors (28198036).

31221044 is a wasteful number, since it uses less digits than its factorization.

31221044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12467 (or 12465 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 31221044 is about 5587.5794401512. The cubic root of 31221044 is about 314.8829463463.

Adding to 31221044 its reverse (44012213), we get a palindrome (75233257).

The spelling of 31221044 in words is "thirty-one million, two hundred twenty-one thousand, forty-four".