21004213001 has 2 divisors, whose sum is σ = 21004213002. Its totient is φ = 21004213000.

The previous prime is 21004212989. The next prime is 21004213007. The reversal of 21004213001 is 10031240012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18632523001 + 2371690000 = 136501^2 + 48700^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21004213001 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21004213007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10502106500 + 10502106501.

It is an arithmetic number, because the mean of its divisors is an integer number (10502106501).

Almost surely, 2^21004213001 is an apocalyptic number.

It is an amenable number.

21004213001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21004213001 is an equidigital number, since it uses as much as digits as its factorization.

21004213001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21004213001 its reverse (10031240012), we get a palindrome (31035453013).

The spelling of 21004213001 in words is "twenty-one billion, four million, two hundred thirteen thousand, one".