20559231 has 96 divisors (see below), whose sum is σ = 40857600. Its totient is φ = 9979200.

The previous prime is 20559223. The next prime is 20559233. The reversal of 20559231 is 13295502.

It is not a de Polignac number, because 20559231 - 2³ = 20559223 is a prime.

It is a super-2 number, since 2×20559231² = 845363958622722, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 20559195 and 20559204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20559233) 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 95 ways as a sum of consecutive naturals, for example, 663186 + ... + 663216.

It is an arithmetic number, because the mean of its divisors is an integer number (425600).

Almost surely, 2^20559231 is an apocalyptic number.

20559231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20559231 is a deficient number, since it is larger than the sum of its proper divisors (20298369).

20559231 is a wasteful number, since it uses less digits than its factorization.

20559231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 20559231 is about 4534.2288208691. The cubic root of 20559231 is about 273.9485180418.

The spelling of 20559231 in words is "twenty million, five hundred fifty-nine thousand, two hundred thirty-one".