20968511 has 2 divisors, whose sum is σ = 20968512. Its totient is φ = 20968510.

The previous prime is 20968499. The next prime is 20968513. The reversal of 20968511 is 11586902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20968511 - 2¹⁰ = 20967487 is a prime.

Together with 20968513, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20968513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10484255 + 10484256.

It is an arithmetic number, because the mean of its divisors is an integer number (10484256).

Almost surely, 2^20968511 is an apocalyptic number.

20968511 is a deficient number, since it is larger than the sum of its proper divisors (1).

20968511 is an equidigital number, since it uses as much as digits as its factorization.

20968511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 20968511 is about 4579.1386744671. The cubic root of 20968511 is about 275.7544506186.

The spelling of 20968511 in words is "twenty million, nine hundred sixty-eight thousand, five hundred eleven".