20638005 has 16 divisors (see below), whose sum is σ = 33149184. Its totient is φ = 10964160.

The previous prime is 20638003. The next prime is 20638019. The reversal of 20638005 is 50083602.

It is not a de Polignac number, because 20638005 - 2¹ = 20638003 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20638001) 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, 1527 + ... + 6603.

It is an arithmetic number, because the mean of its divisors is an integer number (2071824).

Almost surely, 2^20638005 is an apocalyptic number.

It is an amenable number.

20638005 is a deficient number, since it is larger than the sum of its proper divisors (12511179).

20638005 is a wasteful number, since it uses less digits than its factorization.

20638005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5356.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20638005 is about 4542.9071088896. The cubic root of 20638005 is about 274.2979558416.

The spelling of 20638005 in words is "twenty million, six hundred thirty-eight thousand, five".