2013921 has 24 divisors (see below), whose sum is σ = 3581760. Its totient is φ = 1061856.

The previous prime is 2013911. The next prime is 2013923. The reversal of 2013921 is 1293102.

2013921 = 260² + 261² + ... + 286².

It is a happy number.

It is not a de Polignac number, because 2013921 - 2⁵ = 2013889 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2013894 and 2013903.

It is not an unprimeable number, because it can be changed into a prime (2013923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 411 + ... + 2048.

It is an arithmetic number, because the mean of its divisors is an integer number (149240).

2^2013921 is an apocalyptic number.

2013921 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2013921 is a deficient number, since it is larger than the sum of its proper divisors (1567839).

2013921 is a wasteful number, since it uses less digits than its factorization.

2013921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2485 (or 2482 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 2013921 is about 1419.1268442250. The cubic root of 2013921 is about 126.2837520450.

The spelling of 2013921 in words is "two million, thirteen thousand, nine hundred twenty-one".