20191873879 has 4 divisors (see below), whose sum is σ = 21379631184. Its totient is φ = 19004116576.

The previous prime is 20191873853. The next prime is 20191873883. The reversal of 20191873879 is 97837819102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20191873879 - 2⁹ = 20191873367 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20191873829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 593878627 + ... + 593878660.

It is an arithmetic number, because the mean of its divisors is an integer number (5344907796).

Almost surely, 2^20191873879 is an apocalyptic number.

20191873879 is a deficient number, since it is larger than the sum of its proper divisors (1187757305).

20191873879 is a wasteful number, since it uses less digits than its factorization.

20191873879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1187757304.

The product of its (nonzero) digits is 1524096, while the sum is 55.

It can be divided in two parts, 2019187 and 3879, that added together give a triangular number (2023066 = T₂₀₁₁).

The spelling of 20191873879 in words is "twenty billion, one hundred ninety-one million, eight hundred seventy-three thousand, eight hundred seventy-nine".