20969289 has 12 divisors (see below), whose sum is σ = 33042672. Its totient is φ = 12708600.

The previous prime is 20969281. The next prime is 20969303. The reversal of 20969289 is 98296902.

It is not a de Polignac number, because 20969289 - 2³ = 20969281 is a prime.

It is a super-2 number, since 2×20969289² = 879422162331042, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20969281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 105807 + ... + 106004.

It is an arithmetic number, because the mean of its divisors is an integer number (2753556).

Almost surely, 2^20969289 is an apocalyptic number.

It is an amenable number.

20969289 is a deficient number, since it is larger than the sum of its proper divisors (12073383).

20969289 is a wasteful number, since it uses less digits than its factorization.

20969289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211828 (or 211825 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 20969289 is about 4579.2236241529. The cubic root of 20969289 is about 275.7578610389.

The spelling of 20969289 in words is "twenty million, nine hundred sixty-nine thousand, two hundred eighty-nine".