2120521 has 4 divisors (see below), whose sum is σ = 2283652. Its totient is φ = 1957392.

The previous prime is 2120513. The next prime is 2120537. The reversal of 2120521 is 1250212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 765625 + 1354896 = 875^2 + 1164^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120521 - 2³ = 2120513 is a prime.

It is a super-2 number, since 2×2120521² = 8993218622882, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 163117 = 2120521 / (2 + 1 + 2 + 0 + 5 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2120551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81546 + ... + 81571.

It is an arithmetic number, because the mean of its divisors is an integer number (570913).

2^2120521 is an apocalyptic number.

It is an amenable number.

2120521 is a deficient number, since it is larger than the sum of its proper divisors (163131).

2120521 is a wasteful number, since it uses less digits than its factorization.

2120521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163130.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 2120521 is about 1456.2008789999. The cubic root of 2120521 is about 128.4736883856.

Adding to 2120521 its reverse (1250212), we get a palindrome (3370733).

The spelling of 2120521 in words is "two million, one hundred twenty thousand, five hundred twenty-one".