20228603437661 has 2 divisors, whose sum is σ = 20228603437662. Its totient is φ = 20228603437660.

The previous prime is 20228603437643. The next prime is 20228603437717. The reversal of 20228603437661 is 16673430682202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12596749656100 + 7631853781561 = 3549190^2 + 2762581^2 .

It is a cyclic number.

It is not a de Polignac number, because 20228603437661 - 2⁴² = 15830556926557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20228603437621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10114301718830 + 10114301718831.

It is an arithmetic number, because the mean of its divisors is an integer number (10114301718831).

Almost surely, 2^{20228603437661} is an apocalyptic number.

It is an amenable number.

20228603437661 is a deficient number, since it is larger than the sum of its proper divisors (1).

20228603437661 is an equidigital number, since it uses as much as digits as its factorization.

20228603437661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3483648, while the sum is 50.

The spelling of 20228603437661 in words is "twenty trillion, two hundred twenty-eight billion, six hundred three million, four hundred thirty-seven thousand, six hundred sixty-one".