31661344 has 144 divisors (see below), whose sum is σ = 80237304. Its totient is φ = 12165120.

The previous prime is 31661309. The next prime is 31661351. The reversal of 31661344 is 44316613.

It can be written as a sum of positive squares in 4 ways, for example, as 30250000 + 1411344 = 5500^2 + 1188^2 .

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 23 ways as a sum of consecutive naturals, for example, 855694 + ... + 855730.

Almost surely, 2^31661344 is an apocalyptic number.

31661344 is a gapful number since it is divisible by the number (34) 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 31661344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40118652).

31661344 is an abundant number, since it is smaller than the sum of its proper divisors (48575960).

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

31661344 is a wasteful number, since it uses less digits than its factorization.

31661344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 80 counting only the distinct ones).

The product of its digits is 5184, while the sum is 28.

The square root of 31661344 is about 5626.8413874926. The cubic root of 31661344 is about 316.3562717831.

Adding to 31661344 its reverse (44316613), we get a palindrome (75977957).

The spelling of 31661344 in words is "thirty-one million, six hundred sixty-one thousand, three hundred forty-four".