20877889 has 2 divisors, whose sum is σ = 20877890. Its totient is φ = 20877888.

The previous prime is 20877881. The next prime is 20877907. The reversal of 20877889 is 98877802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14288400 + 6589489 = 3780^2 + 2567^2 .

It is a cyclic number.

It is not a de Polignac number, because 20877889 - 2³ = 20877881 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20877881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10438944 + 10438945.

It is an arithmetic number, because the mean of its divisors is an integer number (10438945).

Almost surely, 2^20877889 is an apocalyptic number.

It is an amenable number.

20877889 is a deficient number, since it is larger than the sum of its proper divisors (1).

20877889 is an equidigital number, since it uses as much as digits as its factorization.

20877889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 451584, while the sum is 49.

The square root of 20877889 is about 4569.2328677799. The cubic root of 20877889 is about 275.3566238267.

The spelling of 20877889 in words is "twenty million, eight hundred seventy-seven thousand, eight hundred eighty-nine".