2101864 has 8 divisors (see below), whose sum is σ = 3941010. Its totient is φ = 1050928.

The previous prime is 2101849. The next prime is 2101867. The reversal of 2101864 is 4681012.

It can be written as a sum of positive squares in only one way, i.e., 2079364 + 22500 = 1442^2 + 150^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (2101867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131359 + ... + 131374.

2^2101864 is an apocalyptic number.

It is an amenable number.

2101864 is a deficient number, since it is larger than the sum of its proper divisors (1839146).

2101864 is a wasteful number, since it uses less digits than its factorization.

2101864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262739 (or 262735 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 2101864 is about 1449.7806730675. The cubic root of 2101864 is about 128.0957941759.

Adding to 2101864 its reverse (4681012), we get a palindrome (6782876).

The spelling of 2101864 in words is "two million, one hundred one thousand, eight hundred sixty-four".