2123656 has 16 divisors (see below), whose sum is σ = 4006800. Its totient is φ = 1055184.

The previous prime is 2123617. The next prime is 2123663. The reversal of 2123656 is 6563212.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 2123656.

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, 691 + ... + 2173.

It is an arithmetic number, because the mean of its divisors is an integer number (250425).

2^2123656 is an apocalyptic number.

It is an amenable number.

2123656 is a deficient number, since it is larger than the sum of its proper divisors (1883144).

2123656 is a wasteful number, since it uses less digits than its factorization.

2123656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668 (or 1664 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 2123656 is about 1457.2769126010. The cubic root of 2123656 is about 128.5369694837.

Adding to 2123656 its reverse (6563212), we get a palindrome (8686868).

The spelling of 2123656 in words is "two million, one hundred twenty-three thousand, six hundred fifty-six".