2191878055 has 4 divisors (see below), whose sum is σ = 2630253672. Its totient is φ = 1753502440.

The previous prime is 2191878049. The next prime is 2191878061. The reversal of 2191878055 is 5508781912.

2191878055 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an interprime number because it is at equal distance from previous prime (2191878049) and next prime (2191878061).

It is not a de Polignac number, because 2191878055 - 2⁵ = 2191878023 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2191877996 and 2191878014.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219187801 + ... + 219187810.

It is an arithmetic number, because the mean of its divisors is an integer number (657563418).

Almost surely, 2^2191878055 is an apocalyptic number.

2191878055 is a deficient number, since it is larger than the sum of its proper divisors (438375617).

2191878055 is an equidigital number, since it uses as much as digits as its factorization.

2191878055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438375616.

The product of its (nonzero) digits is 201600, while the sum is 46.

The square root of 2191878055 is about 46817.4973167084. The cubic root of 2191878055 is about 1298.9889683455.

The spelling of 2191878055 in words is "two billion, one hundred ninety-one million, eight hundred seventy-eight thousand, fifty-five".