20133556 has 12 divisors (see below), whose sum is σ = 36765792. Its totient is φ = 9629048.

The previous prime is 20133551. The next prime is 20133557. The reversal of 20133556 is 65533102.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20133556.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20133551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109330 + ... + 109513.

It is an arithmetic number, because the mean of its divisors is an integer number (3063816).

Almost surely, 2^20133556 is an apocalyptic number.

It is an amenable number.

20133556 is a deficient number, since it is larger than the sum of its proper divisors (16632236).

20133556 is a wasteful number, since it uses less digits than its factorization.

20133556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218870 (or 218868 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 25.

The square root of 20133556 is about 4487.0431243749. The cubic root of 20133556 is about 272.0446329583.

Adding to 20133556 its reverse (65533102), we get a palindrome (85666658).

The spelling of 20133556 in words is "twenty million, one hundred thirty-three thousand, five hundred fifty-six".