20666590 has 16 divisors (see below), whose sum is σ = 42514272. Its totient is φ = 7085664.

The previous prime is 20666573. The next prime is 20666599. The reversal of 20666590 is 9566602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20666599) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 147549 + ... + 147688.

It is an arithmetic number, because the mean of its divisors is an integer number (2657142).

Almost surely, 2^20666590 is an apocalyptic number.

20666590 is an abundant number, since it is smaller than the sum of its proper divisors (21847682).

20666590 is a wasteful number, since it uses less digits than its factorization.

20666590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295251.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 20666590 is about 4546.0521334450. The cubic root of 20666590 is about 274.4245376800.

The spelling of 20666590 in words is "twenty million, six hundred sixty-six thousand, five hundred ninety".