20996648009 has 2 divisors, whose sum is σ = 20996648010. Its totient is φ = 20996648008.

The previous prime is 20996647967. The next prime is 20996648011. The reversal of 20996648009 is 90084669902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13799670784 + 7196977225 = 117472^2 + 84835^2 .

It is a cyclic number.

It is not a de Polignac number, because 20996648009 - 2²⁰ = 20995599433 is a prime.

It is a super-2 number, since 2×20996648009² (a number of 21 digits) contains 22 as substring.

Together with 20996648011, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20996648039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10498324004 + 10498324005.

It is an arithmetic number, because the mean of its divisors is an integer number (10498324005).

Almost surely, 2^20996648009 is an apocalyptic number.

It is an amenable number.

20996648009 is a deficient number, since it is larger than the sum of its proper divisors (1).

20996648009 is an equidigital number, since it uses as much as digits as its factorization.

20996648009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1679616, while the sum is 53.

The spelling of 20996648009 in words is "twenty billion, nine hundred ninety-six million, six hundred forty-eight thousand, nine".