20502566 has 16 divisors (see below), whose sum is σ = 35234304. Its totient is φ = 8765064.

The previous prime is 20502553. The next prime is 20502569. The reversal of 20502566 is 66520502.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20502569) 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 in 7 ways as a sum of consecutive naturals, for example, 4901 + ... + 8063.

It is an arithmetic number, because the mean of its divisors is an integer number (2202144).

Almost surely, 2^20502566 is an apocalyptic number.

20502566 is a deficient number, since it is larger than the sum of its proper divisors (14731738).

20502566 is a wasteful number, since it uses less digits than its factorization.

20502566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3635.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 20502566 is about 4527.9759274978. The cubic root of 20502566 is about 273.6966023884.

The spelling of 20502566 in words is "twenty million, five hundred two thousand, five hundred sixty-six".