20205638 has 8 divisors (see below), whose sum is σ = 31626288. Its totient is φ = 9663544.

The previous prime is 20205623. The next prime is 20205697. The reversal of 20205638 is 83650202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219581 + ... + 219672.

It is an arithmetic number, because the mean of its divisors is an integer number (3953286).

Almost surely, 2^20205638 is an apocalyptic number.

20205638 is a deficient number, since it is larger than the sum of its proper divisors (11420650).

20205638 is a wasteful number, since it uses less digits than its factorization.

20205638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439278.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 20205638 is about 4495.0681863571. The cubic root of 20205638 is about 272.3689036388.

The spelling of 20205638 in words is "twenty million, two hundred five thousand, six hundred thirty-eight".