20855342139 has 8 divisors (see below), whose sum is σ = 27825387072. Its totient is φ = 13894429320.

The previous prime is 20855342107. The next prime is 20855342147. The reversal of 20855342139 is 93124355802.

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

It is not a de Polignac number, because 20855342139 - 2⁵ = 20855342107 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 20855342139.

It is not an unprimeable number, because it can be changed into a prime (20855342939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2277697 + ... + 2286834.

It is an arithmetic number, because the mean of its divisors is an integer number (3478173384).

Almost surely, 2^20855342139 is an apocalyptic number.

20855342139 is a deficient number, since it is larger than the sum of its proper divisors (6970044933).

20855342139 is a wasteful number, since it uses less digits than its factorization.

20855342139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4566057.

The product of its (nonzero) digits is 259200, while the sum is 42.

The spelling of 20855342139 in words is "twenty billion, eight hundred fifty-five million, three hundred forty-two thousand, one hundred thirty-nine".