2145171856 has 15 divisors (see below), whose sum is σ = 4156629451. Its totient is φ = 1072493296.

The previous prime is 2145171827. The next prime is 2145171857. The reversal of 2145171856 is 6581715412.

The square root of 2145171856 is 46316.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2145171857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 179475 + ... + 191053.

Almost surely, 2^2145171856 is an apocalyptic number.

2145171856 is the 46316-th square number.

It is an amenable number.

2145171856 is a deficient number, since it is larger than the sum of its proper divisors (2011457595).

2145171856 is an frugal number, since it uses more digits than its factorization.

2145171856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23166 (or 11581 counting only the distinct ones).

The product of its digits is 67200, while the sum is 40.

The cubic root of 2145171856 is about 1289.6960315791.

The spelling of 2145171856 in words is "two billion, one hundred forty-five million, one hundred seventy-one thousand, eight hundred fifty-six".