7121021 has 2 divisors, whose sum is σ = 7121022. Its totient is φ = 7121020.

The previous prime is 7120999. The next prime is 7121033. The reversal of 7121021 is 1201217.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5692996 + 1428025 = 2386^2 + 1195^2 .

It is an emirp because it is prime and its reverse (1201217) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7121021 - 2²² = 2926717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 7120987 and 7121005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7121071) 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 as a sum of consecutive naturals, namely, 3560510 + 3560511.

It is an arithmetic number, because the mean of its divisors is an integer number (3560511).

Almost surely, 2^7121021 is an apocalyptic number.

It is an amenable number.

7121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

7121021 is an equidigital number, since it uses as much as digits as its factorization.

7121021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28, while the sum is 14.

The square root of 7121021 is about 2668.5241239307. The cubic root of 7121021 is about 192.3892295756.

Adding to 7121021 its reverse (1201217), we get a palindrome (8322238).

The spelling of 7121021 in words is "seven million, one hundred twenty-one thousand, twenty-one".