20121221033 has 2 divisors, whose sum is σ = 20121221034. Its totient is φ = 20121221032.

The previous prime is 20121220981. The next prime is 20121221041. The reversal of 20121221033 is 33012212102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17656297129 + 2464923904 = 132877^2 + 49648^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121221033 - 2²⁴ = 20104443817 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121221333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060610516 + 10060610517.

It is an arithmetic number, because the mean of its divisors is an integer number (10060610517).

Almost surely, 2^20121221033 is an apocalyptic number.

It is an amenable number.

20121221033 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121221033 is an equidigital number, since it uses as much as digits as its factorization.

20121221033 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 20121221033 its reverse (33012212102), we get a palindrome (53133433135).

The spelling of 20121221033 in words is "twenty billion, one hundred twenty-one million, two hundred twenty-one thousand, thirty-three".