31433216 has 60 divisors (see below), whose sum is σ = 65936442. Its totient is φ = 14966784.

The previous prime is 31433173. The next prime is 31433219. The reversal of 31433216 is 61233413.

It can be written as a sum of positive squares in 3 ways, for example, as 28047616 + 3385600 = 5296^2 + 1840^2 .

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 31433191 and 31433200.

It is not an unprimeable number, because it can be changed into a prime (31433219) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 430556 + ... + 430628.

Almost surely, 2^31433216 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 31433216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32968221).

31433216 is an abundant number, since it is smaller than the sum of its proper divisors (34503226).

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

31433216 is an frugal number, since it uses more digits than its factorization.

31433216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149 (or 104 counting only the distinct ones).

The product of its digits is 1296, while the sum is 23.

The square root of 31433216 is about 5606.5333317479. The cubic root of 31433216 is about 315.5946305583.

Adding to 31433216 its reverse (61233413), we get a palindrome (92666629).

The spelling of 31433216 in words is "thirty-one million, four hundred thirty-three thousand, two hundred sixteen".