31301021 has 2 divisors, whose sum is σ = 31301022. Its totient is φ = 31301020.

The previous prime is 31301003. The next prime is 31301057. The reversal of 31301021 is 12010313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23522500 + 7778521 = 4850^2 + 2789^2 .

It is a cyclic number.

It is not a de Polignac number, because 31301021 - 2⁶ = 31300957 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 31300993 and 31301011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31301071) 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, 15650510 + 15650511.

It is an arithmetic number, because the mean of its divisors is an integer number (15650511).

Almost surely, 2^31301021 is an apocalyptic number.

It is an amenable number.

31301021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31301021 is an equidigital number, since it uses as much as digits as its factorization.

31301021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 31301021 is about 5594.7315395826. The cubic root of 31301021 is about 315.1515890858.

Adding to 31301021 its reverse (12010313), we get a palindrome (43311334).

The spelling of 31301021 in words is "thirty-one million, three hundred one thousand, twenty-one".