20115224021 has 2 divisors, whose sum is σ = 20115224022. Its totient is φ = 20115224020.

The previous prime is 20115224009. The next prime is 20115224023. The reversal of 20115224021 is 12042251102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17979859921 + 2135364100 = 134089^2 + 46210^2 .

It is a cyclic number.

It is not a de Polignac number, because 20115224021 - 2⁶ = 20115223957 is a prime.

Together with 20115224023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20115223984 and 20115224002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20115224023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10057612010 + 10057612011.

It is an arithmetic number, because the mean of its divisors is an integer number (10057612011).

Almost surely, 2^20115224021 is an apocalyptic number.

It is an amenable number.

20115224021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20115224021 is an equidigital number, since it uses as much as digits as its factorization.

20115224021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 20.

Adding to 20115224021 its reverse (12042251102), we get a palindrome (32157475123).

The spelling of 20115224021 in words is "twenty billion, one hundred fifteen million, two hundred twenty-four thousand, twenty-one".