2173661 has 12 divisors (see below), whose sum is σ = 2601312. Its totient is φ = 1779096.

The previous prime is 2173651. The next prime is 2173663. The reversal of 2173661 is 1663712.

2173661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2173661 - 2¹⁴ = 2157277 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 2173661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2173663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3410 + ... + 3996.

It is an arithmetic number, because the mean of its divisors is an integer number (216776).

2^2173661 is an apocalyptic number.

It is an amenable number.

2173661 is a deficient number, since it is larger than the sum of its proper divisors (427651).

2173661 is an equidigital number, since it uses as much as digits as its factorization.

2173661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640 (or 617 counting only the distinct ones).

The product of its digits is 1512, while the sum is 26.

The square root of 2173661 is about 1474.3340869694. The cubic root of 2173661 is about 129.5380249393.

The spelling of 2173661 in words is "two million, one hundred seventy-three thousand, six hundred sixty-one".