20988377017 has 2 divisors, whose sum is σ = 20988377018. Its totient is φ = 20988377016.

The previous prime is 20988376979. The next prime is 20988377023. The reversal of 20988377017 is 71077388902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17210553721 + 3777823296 = 131189^2 + 61464^2 .

It is a cyclic number.

It is not a de Polignac number, because 20988377017 - 2⁷ = 20988376889 is a prime.

It is not a weakly prime, because it can be changed into another prime (20988377057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10494188508 + 10494188509.

It is an arithmetic number, because the mean of its divisors is an integer number (10494188509).

Almost surely, 2^20988377017 is an apocalyptic number.

It is an amenable number.

20988377017 is a deficient number, since it is larger than the sum of its proper divisors (1).

20988377017 is an equidigital number, since it uses as much as digits as its factorization.

20988377017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1185408, while the sum is 52.

The spelling of 20988377017 in words is "twenty billion, nine hundred eighty-eight million, three hundred seventy-seven thousand, seventeen".