2013021 has 24 divisors (see below), whose sum is σ = 3144960. Its totient is φ = 1236096.

The previous prime is 2013019. The next prime is 2013023. The reversal of 2013021 is 1203102.

It is a happy number.

2013021 is a nontrivial binomial coefficient, being equal to C(2007, 2).

It is an interprime number because it is at equal distance from previous prime (2013019) and next prime (2013023).

It is not a de Polignac number, because 2013021 - 2¹ = 2013019 is a prime.

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

It is a junction number, because it is equal to n+sod(n) for n = 2012994 and 2013012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2013023) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8916 + ... + 9138.

It is an arithmetic number, because the mean of its divisors is an integer number (131040).

2^2013021 is an apocalyptic number.

2013021 is the 2006-th triangular number.

It is an amenable number.

2013021 is a deficient number, since it is larger than the sum of its proper divisors (1131939).

2013021 is a wasteful number, since it uses less digits than its factorization.

2013021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305 (or 302 counting only the distinct ones).

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

The square root of 2013021 is about 1418.8097123998. The cubic root of 2013021 is about 126.2649376176.

Adding to 2013021 its reverse (1203102), we get a palindrome (3216123).

It can be divided in two parts, 20 and 13021, that added together give a triangular number (13041 = T₁₆₁).

The spelling of 2013021 in words is "two million, thirteen thousand, twenty-one".