20221121021 has 2 divisors, whose sum is σ = 20221121022. Its totient is φ = 20221121020.

The previous prime is 20221120967. The next prime is 20221121027. The reversal of 20221121021 is 12012112202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20049144025 + 171976996 = 141595^2 + 13114^2 .

It is a cyclic number.

It is not a de Polignac number, because 20221121021 - 2¹⁸ = 20220858877 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20221120987 and 20221121005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20221121027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10110560510 + 10110560511.

It is an arithmetic number, because the mean of its divisors is an integer number (10110560511).

Almost surely, 2^20221121021 is an apocalyptic number.

It is an amenable number.

20221121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20221121021 is an equidigital number, since it uses as much as digits as its factorization.

20221121021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 20221121021 its reverse (12012112202), we get a palindrome (32233233223).

The spelling of 20221121021 in words is "twenty billion, two hundred twenty-one million, one hundred twenty-one thousand, twenty-one".