2190521 has 2 divisors, whose sum is σ = 2190522. Its totient is φ = 2190520.

The previous prime is 2190499. The next prime is 2190523. The reversal of 2190521 is 1250912.

2190521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2190400 + 121 = 1480^2 + 11^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2190521 is a prime.

It is a Sophie Germain prime.

Together with 2190523, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2190493 and 2190502.

It is not a weakly prime, because it can be changed into another prime (2190523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1095260 + 1095261.

It is an arithmetic number, because the mean of its divisors is an integer number (1095261).

2^2190521 is an apocalyptic number.

It is an amenable number.

2190521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2190521 is an equidigital number, since it uses as much as digits as its factorization.

2190521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 2190521 is about 1480.0408778139. The cubic root of 2190521 is about 129.8720832474.

The spelling of 2190521 in words is "two million, one hundred ninety thousand, five hundred twenty-one".