2100321 has 12 divisors (see below), whose sum is σ = 3063060. Its totient is φ = 1386720.

The previous prime is 2100313. The next prime is 2100353. The reversal of 2100321 is 1230012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1782225 + 318096 = 1335^2 + 564^2 .

It is not a de Polignac number, because 2100321 - 2³ = 2100313 is a prime.

It is a super-2 number, since 2×2100321² = 8822696606082, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90 + ... + 2051.

It is an arithmetic number, because the mean of its divisors is an integer number (255255).

2^2100321 is an apocalyptic number.

It is an amenable number.

2100321 is a deficient number, since it is larger than the sum of its proper divisors (962739).

2100321 is a wasteful number, since it uses less digits than its factorization.

2100321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256 (or 2253 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 2100321 is about 1449.2484259091. The cubic root of 2100321 is about 128.0644410221.

Adding to 2100321 its reverse (1230012), we get a palindrome (3330333).

The spelling of 2100321 in words is "two million, one hundred thousand, three hundred twenty-one".