103210021 has 2 divisors, whose sum is σ = 103210022. Its totient is φ = 103210020.

The previous prime is 103210013. The next prime is 103210069. The reversal of 103210021 is 120012301.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87890625 + 15319396 = 9375^2 + 3914^2 .

It is an emirp because it is prime and its reverse (120012301) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 103210021 - 2³ = 103210013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (103210721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51605010 + 51605011.

It is an arithmetic number, because the mean of its divisors is an integer number (51605011).

Almost surely, 2^103210021 is an apocalyptic number.

It is an amenable number.

103210021 is a deficient number, since it is larger than the sum of its proper divisors (1).

103210021 is an equidigital number, since it uses as much as digits as its factorization.

103210021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 103210021 is about 10159.2332879996. The cubic root of 103210021 is about 469.0732015528.

Adding to 103210021 its reverse (120012301), we get a palindrome (223222322).

The spelling of 103210021 in words is "one hundred three million, two hundred ten thousand, twenty-one".