2171745656 has 16 divisors (see below), whose sum is σ = 4074783840. Its totient is φ = 1085136640.

The previous prime is 2171745601. The next prime is 2171745671. The reversal of 2171745656 is 6565471712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79385 + ... + 103176.

It is an arithmetic number, because the mean of its divisors is an integer number (254673990).

Almost surely, 2^2171745656 is an apocalyptic number.

It is an amenable number.

2171745656 is a deficient number, since it is larger than the sum of its proper divisors (1903038184).

2171745656 is a wasteful number, since it uses less digits than its factorization.

2171745656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184054 (or 184050 counting only the distinct ones).

The product of its digits is 352800, while the sum is 44.

The square root of 2171745656 is about 46601.9919745927. The cubic root of 2171745656 is about 1294.9996583234. Note that the first 3 decimals are identical.

The spelling of 2171745656 in words is "two billion, one hundred seventy-one million, seven hundred forty-five thousand, six hundred fifty-six".