2157845905 has 8 divisors (see below), whose sum is σ = 2644509312. Its totient is φ = 1689547248.

The previous prime is 2157845873. The next prime is 2157845917. The reversal of 2157845905 is 5095487512.

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

It is a cyclic number.

It is not a de Polignac number, because 2157845905 - 2⁵ = 2157845873 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 4590927 + ... + 4591396.

It is an arithmetic number, because the mean of its divisors is an integer number (330563664).

Almost surely, 2^2157845905 is an apocalyptic number.

It is an amenable number.

2157845905 is a deficient number, since it is larger than the sum of its proper divisors (486663407).

2157845905 is an equidigital number, since it uses as much as digits as its factorization.

2157845905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9182375.

The product of its (nonzero) digits is 504000, while the sum is 46.

The square root of 2157845905 is about 46452.6200014596. The cubic root of 2157845905 is about 1292.2309621143.

The spelling of 2157845905 in words is "two billion, one hundred fifty-seven million, eight hundred forty-five thousand, nine hundred five".