2112171685791 has 4 divisors (see below), whose sum is σ = 2816228914392. Its totient is φ = 1408114457192.

The previous prime is 2112171685783. The next prime is 2112171685823. The reversal of 2112171685791 is 1975861712112.

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 2112171685791 - 2³ = 2112171685783 is a prime.

It is a super-2 number, since 2×2112171685791² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2112171685391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 352028614296 + ... + 352028614301.

It is an arithmetic number, because the mean of its divisors is an integer number (704057228598).

Almost surely, 2^{2112171685791} is an apocalyptic number.

2112171685791 is a deficient number, since it is larger than the sum of its proper divisors (704057228601).

2112171685791 is an equidigital number, since it uses as much as digits as its factorization.

2112171685791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704057228600.

The product of its digits is 423360, while the sum is 51.

The spelling of 2112171685791 in words is "two trillion, one hundred twelve billion, one hundred seventy-one million, six hundred eighty-five thousand, seven hundred ninety-one".