21221003201 has 2 divisors, whose sum is σ = 21221003202. Its totient is φ = 21221003200.

The previous prime is 21221003173. The next prime is 21221003267. The reversal of 21221003201 is 10230012212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21126913201 + 94090000 = 145351^2 + 9700^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221003201 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 (21221003101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610501600 + 10610501601.

It is an arithmetic number, because the mean of its divisors is an integer number (10610501601).

Almost surely, 2^21221003201 is an apocalyptic number.

It is an amenable number.

21221003201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221003201 is an equidigital number, since it uses as much as digits as its factorization.

21221003201 is an evil number, because the sum of its binary digits is even.

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

Adding to 21221003201 its reverse (10230012212), we get a palindrome (31451015413).

The spelling of 21221003201 in words is "twenty-one billion, two hundred twenty-one million, three thousand, two hundred one".