20221220161 has 2 divisors, whose sum is σ = 20221220162. Its totient is φ = 20221220160.

The previous prime is 20221220153. The next prime is 20221220167. The reversal of 20221220161 is 16102212202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16661904561 + 3559315600 = 129081^2 + 59660^2 .

It is a cyclic number.

It is not a de Polignac number, because 20221220161 - 2³ = 20221220153 is a prime.

It is not a weakly prime, because it can be changed into another prime (20221220167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10110610080 + 10110610081.

It is an arithmetic number, because the mean of its divisors is an integer number (10110610081).

Almost surely, 2^20221220161 is an apocalyptic number.

It is an amenable number.

20221220161 is a deficient number, since it is larger than the sum of its proper divisors (1).

20221220161 is an equidigital number, since it uses as much as digits as its factorization.

20221220161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 20221220161 its reverse (16102212202), we get a palindrome (36323432363).

The spelling of 20221220161 in words is "twenty billion, two hundred twenty-one million, two hundred twenty thousand, one hundred sixty-one".