20559969 has 6 divisors (see below), whose sum is σ = 29697746. Its totient is φ = 13706640.

The previous prime is 20559949. The next prime is 20559991. The reversal of 20559969 is 96995502.

20559969 is a `hidden beast` number, since 2 + 0 + 559 + 96 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15210000 + 5349969 = 3900^2 + 2313^2 .

It is not a de Polignac number, because 20559969 - 2⁷ = 20559841 is a prime.

It is a super-2 number, since 2×20559969² = 845424650561922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20559949) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1142212 + ... + 1142229.

Almost surely, 2^20559969 is an apocalyptic number.

It is an amenable number.

20559969 is a deficient number, since it is larger than the sum of its proper divisors (9137777).

20559969 is a wasteful number, since it uses less digits than its factorization.

20559969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2284447 (or 2284444 counting only the distinct ones).

The product of its (nonzero) digits is 218700, while the sum is 45.

The square root of 20559969 is about 4534.3102011221. The cubic root of 20559969 is about 273.9517959139.

It can be divided in two parts, 20559 and 969, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 20559969 in words is "twenty million, five hundred fifty-nine thousand, nine hundred sixty-nine".