20268138 has 16 divisors (see below), whose sum is σ = 44221536. Its totient is φ = 6141840.

The previous prime is 20268137. The next prime is 20268163. The reversal of 20268138 is 83186202.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20268137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153481 + ... + 153612.

It is an arithmetic number, because the mean of its divisors is an integer number (2763846).

Almost surely, 2^20268138 is an apocalyptic number.

20268138 is an abundant number, since it is smaller than the sum of its proper divisors (23953398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20268138 is a wasteful number, since it uses less digits than its factorization.

20268138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307109.

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 20268138 is about 4502.0148822499. The cubic root of 20268138 is about 272.6494447217.

The spelling of 20268138 in words is "twenty million, two hundred sixty-eight thousand, one hundred thirty-eight".