20228603437921 has 2 divisors, whose sum is σ = 20228603437922. Its totient is φ = 20228603437920.

The previous prime is 20228603437909. The next prime is 20228603438039. The reversal of 20228603437921 is 12973430682202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16780288140625 + 3448315297296 = 4096375^2 + 1856964^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20228603437921 is a prime.

It is not a weakly prime, because it can be changed into another prime (20228603437621) 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, 10114301718960 + 10114301718961.

It is an arithmetic number, because the mean of its divisors is an integer number (10114301718961).

Almost surely, 2^{20228603437921} is an apocalyptic number.

It is an amenable number.

20228603437921 is a deficient number, since it is larger than the sum of its proper divisors (1).

20228603437921 is an equidigital number, since it uses as much as digits as its factorization.

20228603437921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1741824, while the sum is 49.

The spelling of 20228603437921 in words is "twenty trillion, two hundred twenty-eight billion, six hundred three million, four hundred thirty-seven thousand, nine hundred twenty-one".