20426569 has 4 divisors (see below), whose sum is σ = 20924820. Its totient is φ = 19928320.

The previous prime is 20426561. The next prime is 20426573. The reversal of 20426569 is 96562402.

20426569 is nontrivially palindromic in base 8.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3286969 + 17139600 = 1813^2 + 4140^2 .

It is a cyclic number.

It is not a de Polignac number, because 20426569 - 2³ = 20426561 is a prime.

It is a super-2 number, since 2×20426569² = 834489442223522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20426561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 249064 + ... + 249145.

It is an arithmetic number, because the mean of its divisors is an integer number (5231205).

Almost surely, 2^20426569 is an apocalyptic number.

It is an amenable number.

20426569 is a deficient number, since it is larger than the sum of its proper divisors (498251).

20426569 is an equidigital number, since it uses as much as digits as its factorization.

20426569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498250.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 20426569 is about 4519.5761969459. The cubic root of 20426569 is about 273.3580126768.

The spelling of 20426569 in words is "twenty million, four hundred twenty-six thousand, five hundred sixty-nine".