20138855 has 8 divisors (see below), whose sum is σ = 26363664. Its totient is φ = 14646400.

The previous prime is 20138851. The next prime is 20138903. The reversal of 20138855 is 55883102.

It is a happy number.

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

It is not a de Polignac number, because 20138855 - 2² = 20138851 is a prime.

It is a super-2 number, since 2×20138855² = 811146961422050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20138851) 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, 183026 + ... + 183135.

It is an arithmetic number, because the mean of its divisors is an integer number (3295458).

Almost surely, 2^20138855 is an apocalyptic number.

20138855 is a deficient number, since it is larger than the sum of its proper divisors (6224809).

20138855 is a wasteful number, since it uses less digits than its factorization.

20138855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366177.

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 20138855 is about 4487.6335634720. The cubic root of 20138855 is about 272.0684975629.

The spelling of 20138855 in words is "twenty million, one hundred thirty-eight thousand, eight hundred fifty-five".