20776289 has 6 divisors (see below), whose sum is σ = 21048930. Its totient is φ = 20507136.

The previous prime is 20776279. The next prime is 20776307. The reversal of 20776289 is 98267702.

It can be written as a sum of positive squares in only one way, i.e., 16875664 + 3900625 = 4108^2 + 1975^2 .

It is not a de Polignac number, because 20776289 - 2⁸ = 20776033 is a prime.

It is a super-2 number, since 2×20776289² = 863308369223042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20776219) 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 in 5 ways as a sum of consecutive naturals, for example, 4577 + ... + 7905.

It is an arithmetic number, because the mean of its divisors is an integer number (3508155).

Almost surely, 2^20776289 is an apocalyptic number.

It is an amenable number.

20776289 is a deficient number, since it is larger than the sum of its proper divisors (272641).

20776289 is an frugal number, since it uses more digits than its factorization.

20776289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3487 (or 3408 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 41.

The square root of 20776289 is about 4558.1014688135. The cubic root of 20776289 is about 274.9092328544.

The spelling of 20776289 in words is "twenty million, seven hundred seventy-six thousand, two hundred eighty-nine".