31424321 has 2 divisors, whose sum is σ = 31424322. Its totient is φ = 31424320.

The previous prime is 31424303. The next prime is 31424329. The reversal of 31424321 is 12342413.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24850225 + 6574096 = 4985^2 + 2564^2 .

It is a cyclic number.

It is not a de Polignac number, because 31424321 - 2¹⁰ = 31423297 is a prime.

It is a super-2 number, since 2×31424321² = 1974975900622082, which contains 22 as substring.

It is a Chen prime.

It is equal to p_1940510 and since 31424321 and 1940510 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 31424293 and 31424302.

It is not a weakly prime, because it can be changed into another prime (31424329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15712160 + 15712161.

It is an arithmetic number, because the mean of its divisors is an integer number (15712161).

Almost surely, 2^31424321 is an apocalyptic number.

It is an amenable number.

31424321 is a deficient number, since it is larger than the sum of its proper divisors (1).

31424321 is an equidigital number, since it uses as much as digits as its factorization.

31424321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 20.

The square root of 31424321 is about 5605.7400046738. The cubic root of 31424321 is about 315.5648586648.

Adding to 31424321 its reverse (12342413), we get a palindrome (43766734).

The spelling of 31424321 in words is "thirty-one million, four hundred twenty-four thousand, three hundred twenty-one".