20505590 has 32 divisors (see below), whose sum is σ = 42341184. Its totient is φ = 7004160.

The previous prime is 20505571. The next prime is 20505593. The reversal of 20505590 is 9550502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505593) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31670 + ... + 32310.

It is an arithmetic number, because the mean of its divisors is an integer number (1323162).

Almost surely, 2^20505590 is an apocalyptic number.

20505590 is an abundant number, since it is smaller than the sum of its proper divisors (21835594).

20505590 is a wasteful number, since it uses less digits than its factorization.

20505590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1112.

The product of its (nonzero) digits is 2250, while the sum is 26.

The square root of 20505590 is about 4528.3098392226. The cubic root of 20505590 is about 273.7100579048.

The spelling of 20505590 in words is "twenty million, five hundred five thousand, five hundred ninety".