31033421 has 2 divisors, whose sum is σ = 31033422. Its totient is φ = 31033420.

The previous prime is 31033411. The next prime is 31033423. The reversal of 31033421 is 12433013.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21949225 + 9084196 = 4685^2 + 3014^2 .

It is a cyclic number.

It is not a de Polignac number, because 31033421 - 2⁶ = 31033357 is a prime.

It is a Sophie Germain prime.

Together with 31033423, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31033421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31033423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15516710 + 15516711.

It is an arithmetic number, because the mean of its divisors is an integer number (15516711).

Almost surely, 2^31033421 is an apocalyptic number.

It is an amenable number.

31033421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31033421 is an equidigital number, since it uses as much as digits as its factorization.

31033421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 31033421 is about 5570.7648487438. The cubic root of 31033421 is about 314.2509151061.

Adding to 31033421 its reverse (12433013), we get a palindrome (43466434).

The spelling of 31033421 in words is "thirty-one million, thirty-three thousand, four hundred twenty-one".