2620021 has 2 divisors, whose sum is σ = 2620022. Its totient is φ = 2620020.

The previous prime is 2620019. The next prime is 2620031. The reversal of 2620021 is 1200262.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2002225 + 617796 = 1415^2 + 786^2 .

It is a cyclic number.

It is not a de Polignac number, because 2620021 - 2¹ = 2620019 is a prime.

Together with 2620019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 2619983 and 2620010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2620031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1310010 + 1310011.

It is an arithmetic number, because the mean of its divisors is an integer number (1310011).

2^2620021 is an apocalyptic number.

It is an amenable number.

2620021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2620021 is an equidigital number, since it uses as much as digits as its factorization.

2620021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 2620021 is about 1618.6478925325. The cubic root of 2620021 is about 137.8589365796.

Adding to 2620021 its reverse (1200262), we get a palindrome (3820283).

The spelling of 2620021 in words is "two million, six hundred twenty thousand, twenty-one".