1244210021 has 2 divisors, whose sum is σ = 1244210022. Its totient is φ = 1244210020.

The previous prime is 1244209973. The next prime is 1244210053. The reversal of 1244210021 is 1200124421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 909685921 + 334524100 = 30161^2 + 18290^2 .

It is a cyclic number.

It is not a de Polignac number, because 1244210021 - 2¹⁸ = 1243947877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1244210081) 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, 622105010 + 622105011.

It is an arithmetic number, because the mean of its divisors is an integer number (622105011).

Almost surely, 2^1244210021 is an apocalyptic number.

It is an amenable number.

1244210021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1244210021 is an equidigital number, since it uses as much as digits as its factorization.

1244210021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 1244210021 is about 35273.3613510252. The cubic root of 1244210021 is about 1075.5515528403.

Adding to 1244210021 its reverse (1200124421), we get a palindrome (2444334442).

The spelling of 1244210021 in words is "one billion, two hundred forty-four million, two hundred ten thousand, twenty-one".