2102661 has 24 divisors (see below), whose sum is σ = 3373344. Its totient is φ = 1251360.

The previous prime is 2102651. The next prime is 2102687. The reversal of 2102661 is 1662012.

It is a happy number.

2102661 is a `hidden beast` number, since 2 + 1 + 0 + 2 + 661 = 666.

It is not a de Polignac number, because 2102661 - 2⁵ = 2102629 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2102651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6475 + ... + 6791.

It is an arithmetic number, because the mean of its divisors is an integer number (140556).

2^2102661 is an apocalyptic number.

It is an amenable number.

2102661 is a deficient number, since it is larger than the sum of its proper divisors (1270683).

2102661 is a wasteful number, since it uses less digits than its factorization.

2102661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401 (or 398 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 2102661 is about 1450.0555161786. The cubic root of 2102661 is about 128.1119828933. Note that the first 3 decimals are identical.

Adding to 2102661 its reverse (1662012), we get a palindrome (3764673).

The spelling of 2102661 in words is "two million, one hundred two thousand, six hundred sixty-one".