7922021 has 2 divisors, whose sum is σ = 7922022. Its totient is φ = 7922020.

The previous prime is 7921999. The next prime is 7922023. The reversal of 7922021 is 1202297.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7896100 + 25921 = 2810^2 + 161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7922021 is a prime.

Together with 7922023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7922023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3961010 + 3961011.

It is an arithmetic number, because the mean of its divisors is an integer number (3961011).

Almost surely, 2^7922021 is an apocalyptic number.

It is an amenable number.

7922021 is a deficient number, since it is larger than the sum of its proper divisors (1).

7922021 is an equidigital number, since it uses as much as digits as its factorization.

7922021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 7922021 is about 2814.6084985305. The cubic root of 7922021 is about 199.3480521290.

The spelling of 7922021 in words is "seven million, nine hundred twenty-two thousand, twenty-one".