2171854945 has 32 divisors (see below), whose sum is σ = 2959084800. Its totient is φ = 1517025024.

The previous prime is 2171854943. The next prime is 2171854963. The reversal of 2171854945 is 5494581712.

It is a cyclic number.

It is not a de Polignac number, because 2171854945 - 2¹ = 2171854943 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2171854895 and 2171854904.

It is not an unprimeable number, because it can be changed into a prime (2171854943) 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 31 ways as a sum of consecutive naturals, for example, 1213111 + ... + 1214899.

It is an arithmetic number, because the mean of its divisors is an integer number (92471400).

Almost surely, 2^2171854945 is an apocalyptic number.

It is an amenable number.

2171854945 is a deficient number, since it is larger than the sum of its proper divisors (787229855).

2171854945 is a wasteful number, since it uses less digits than its factorization.

2171854945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2809.

The product of its digits is 403200, while the sum is 46.

The square root of 2171854945 is about 46603.1645384731. The cubic root of 2171854945 is about 1295.0213807634.

The spelling of 2171854945 in words is "two billion, one hundred seventy-one million, eight hundred fifty-four thousand, nine hundred forty-five".