20243556 has 36 divisors (see below), whose sum is σ = 51377872. Its totient is φ = 6720624.

The previous prime is 20243533. The next prime is 20243563. The reversal of 20243556 is 65534202.

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 9195 + ... + 11181.

Almost surely, 2^20243556 is an apocalyptic number.

It is an amenable number.

20243556 is an abundant number, since it is smaller than the sum of its proper divisors (31134316).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20243556 is a wasteful number, since it uses less digits than its factorization.

20243556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2280 (or 2275 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The square root of 20243556 is about 4499.2839430292. The cubic root of 20243556 is about 272.5391734498.

Adding to 20243556 its reverse (65534202), we get a palindrome (85777758).

The spelling of 20243556 in words is "twenty million, two hundred forty-three thousand, five hundred fifty-six".