20022209981 has 2 divisors, whose sum is σ = 20022209982. Its totient is φ = 20022209980.

The previous prime is 20022209953. The next prime is 20022209983. The reversal of 20022209981 is 18990222002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19911749881 + 110460100 = 141109^2 + 10510^2 .

It is a cyclic number.

It is not a de Polignac number, because 20022209981 - 2⁶ = 20022209917 is a prime.

It is a super-2 number, since 2×20022209981² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 20022209983, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20022209983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10011104990 + 10011104991.

It is an arithmetic number, because the mean of its divisors is an integer number (10011104991).

Almost surely, 2^20022209981 is an apocalyptic number.

It is an amenable number.

20022209981 is a deficient number, since it is larger than the sum of its proper divisors (1).

20022209981 is an equidigital number, since it uses as much as digits as its factorization.

20022209981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 35.

The spelling of 20022209981 in words is "twenty billion, twenty-two million, two hundred nine thousand, nine hundred eighty-one".