2158677217 has 4 divisors (see below), whose sum is σ = 2163360276. Its totient is φ = 2153994160.

The previous prime is 2158677203. The next prime is 2158677299. The reversal of 2158677217 is 7127768512.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1565072721 + 593604496 = 39561^2 + 24364^2 .

It is a cyclic number.

It is not a de Polignac number, because 2158677217 - 2³¹ = 11193569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2158671217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2340838 + ... + 2341759.

It is an arithmetic number, because the mean of its divisors is an integer number (540840069).

Almost surely, 2^2158677217 is an apocalyptic number.

It is an amenable number.

2158677217 is a deficient number, since it is larger than the sum of its proper divisors (4683059).

2158677217 is an equidigital number, since it uses as much as digits as its factorization.

2158677217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4683058.

The product of its digits is 329280, while the sum is 46.

The square root of 2158677217 is about 46461.5670958266. The cubic root of 2158677217 is about 1292.3968851738.

The spelling of 2158677217 in words is "two billion, one hundred fifty-eight million, six hundred seventy-seven thousand, two hundred seventeen".