20533556 has 6 divisors (see below), whose sum is σ = 35933730. Its totient is φ = 10266776.

The previous prime is 20533553. The next prime is 20533571. The reversal of 20533556 is 65533502.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 10824100 + 9709456 = 3290^2 + 3116^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20533553) by changing a digit.

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 as a sum of consecutive naturals, namely, 2566691 + ... + 2566698.

It is an arithmetic number, because the mean of its divisors is an integer number (5988955).

Almost surely, 2^20533556 is an apocalyptic number.

It is an amenable number.

20533556 is a deficient number, since it is larger than the sum of its proper divisors (15400174).

20533556 is a wasteful number, since it uses less digits than its factorization.

20533556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5133393 (or 5133391 counting only the distinct ones).

The product of its (nonzero) digits is 13500, while the sum is 29.

The square root of 20533556 is about 4531.3966941772. The cubic root of 20533556 is about 273.8344320922.

The spelling of 20533556 in words is "twenty million, five hundred thirty-three thousand, five hundred fifty-six".