20742205177 has 2 divisors, whose sum is σ = 20742205178. Its totient is φ = 20742205176.

The previous prime is 20742205157. The next prime is 20742205229. The reversal of 20742205177 is 77150224702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17086672656 + 3655532521 = 130716^2 + 60461^2 .

It is a cyclic number.

It is not a de Polignac number, because 20742205177 - 2⁷ = 20742205049 is a prime.

It is not a weakly prime, because it can be changed into another prime (20742205157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10371102588 + 10371102589.

It is an arithmetic number, because the mean of its divisors is an integer number (10371102589).

Almost surely, 2^20742205177 is an apocalyptic number.

It is an amenable number.

20742205177 is a deficient number, since it is larger than the sum of its proper divisors (1).

20742205177 is an equidigital number, since it uses as much as digits as its factorization.

20742205177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54880, while the sum is 37.

Adding to 20742205177 its reverse (77150224702), we get a palindrome (97892429879).

The spelling of 20742205177 in words is "twenty billion, seven hundred forty-two million, two hundred five thousand, one hundred seventy-seven".