20639146 has 16 divisors (see below), whose sum is σ = 33865920. Its totient is φ = 9355680.

The previous prime is 20639141. The next prime is 20639147. The reversal of 20639146 is 64193602.

It is not an unprimeable number, because it can be changed into a prime (20639141) 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, 8590 + ... + 10726.

It is an arithmetic number, because the mean of its divisors is an integer number (2116620).

Almost surely, 2^20639146 is an apocalyptic number.

20639146 is a deficient number, since it is larger than the sum of its proper divisors (13226774).

20639146 is a wasteful number, since it uses less digits than its factorization.

20639146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2589.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 20639146 is about 4543.0326875337. The cubic root of 20639146 is about 274.3030107262.

The spelling of 20639146 in words is "twenty million, six hundred thirty-nine thousand, one hundred forty-six".