20493556 has 12 divisors (see below), whose sum is σ = 36126468. Its totient is φ = 10171712.

The previous prime is 20493553. The next prime is 20493581. The reversal of 20493556 is 65539402.

It can be written as a sum of positive squares in 2 ways, for example, as 8797156 + 11696400 = 2966^2 + 3420^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20493553) 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, 18151 + ... + 19246.

It is an arithmetic number, because the mean of its divisors is an integer number (3010539).

Almost surely, 2^20493556 is an apocalyptic number.

It is an amenable number.

20493556 is a deficient number, since it is larger than the sum of its proper divisors (15632912).

20493556 is a wasteful number, since it uses less digits than its factorization.

20493556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37538 (or 37536 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 20493556 is about 4526.9808923829. The cubic root of 20493556 is about 273.6565038676.

The spelling of 20493556 in words is "twenty million, four hundred ninety-three thousand, five hundred fifty-six".