2165644 has 12 divisors (see below), whose sum is σ = 4081504. Its totient is φ = 999504.

The previous prime is 2165617. The next prime is 2165651. The reversal of 2165644 is 4465612.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

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, 20772 + ... + 20875.

2^2165644 is an apocalyptic number.

It is an amenable number.

2165644 is a deficient number, since it is larger than the sum of its proper divisors (1915860).

2165644 is a wasteful number, since it uses less digits than its factorization.

2165644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41664 (or 41662 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

The square root of 2165644 is about 1471.6127207931. The cubic root of 2165644 is about 129.3785726413.

Subtracting 2165644 from its reverse (4465612), we obtain a cube (2299968 = 132³).

It can be divided in two parts, 2165 and 644, that added together give a square (2809 = 53²).

The spelling of 2165644 in words is "two million, one hundred sixty-five thousand, six hundred forty-four".