21221000201 has 2 divisors, whose sum is σ = 21221000202. Its totient is φ = 21221000200.

The previous prime is 21221000191. The next prime is 21221000233. The reversal of 21221000201 is 10200012212.

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., 13152649225 + 8068350976 = 114685^2 + 89824^2 .

It is a cyclic number.

It is not a de Polignac number, because 21221000201 - 2²⁶ = 21153891337 is a prime.

It is not a weakly prime, because it can be changed into another prime (21221003201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610500100 + 10610500101.

It is an arithmetic number, because the mean of its divisors is an integer number (10610500101).

Almost surely, 2^21221000201 is an apocalyptic number.

It is an amenable number.

21221000201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221000201 is an equidigital number, since it uses as much as digits as its factorization.

21221000201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21221000201 its reverse (10200012212), we get a palindrome (31421012413).

The spelling of 21221000201 in words is "twenty-one billion, two hundred twenty-one million, two hundred one", and thus it is an aban number.