2690021 has 2 divisors, whose sum is σ = 2690022. Its totient is φ = 2690020.

The previous prime is 2690003. The next prime is 2690027. The reversal of 2690021 is 1200962.

2690021 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., 2608225 + 81796 = 1615^2 + 286^2 .

It is a cyclic number.

It is not a de Polignac number, because 2690021 - 2⁶ = 2689957 is a prime.

It is a Chen prime.

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 2689975 and 2690002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2690027) 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, 1345010 + 1345011.

It is an arithmetic number, because the mean of its divisors is an integer number (1345011).

2^2690021 is an apocalyptic number.

It is an amenable number.

2690021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2690021 is an equidigital number, since it uses as much as digits as its factorization.

2690021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 2690021 is about 1640.1283486362. The cubic root of 2690021 is about 139.0759035433.

Adding to 2690021 its reverse (1200962), we get a palindrome (3890983).

The spelling of 2690021 in words is "two million, six hundred ninety thousand, twenty-one".