20711869 has 2 divisors, whose sum is σ = 20711870. Its totient is φ = 20711868.

The previous prime is 20711861. The next prime is 20711893. The reversal of 20711869 is 96811702.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20520900 + 190969 = 4530^2 + 437^2 .

It is a cyclic number.

It is not a de Polignac number, because 20711869 - 2³ = 20711861 is a prime.

It is a super-2 number, since 2×20711869² = 857963034946322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20711861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10355934 + 10355935.

It is an arithmetic number, because the mean of its divisors is an integer number (10355935).

Almost surely, 2^20711869 is an apocalyptic number.

It is an amenable number.

20711869 is a deficient number, since it is larger than the sum of its proper divisors (1).

20711869 is an equidigital number, since it uses as much as digits as its factorization.

20711869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 20711869 is about 4551.0294439830. The cubic root of 20711869 is about 274.6248062469.

The spelling of 20711869 in words is "twenty million, seven hundred eleven thousand, eight hundred sixty-nine".