7997621 has 2 divisors, whose sum is σ = 7997622. Its totient is φ = 7997620.

The previous prime is 7997581. The next prime is 7997623. The reversal of 7997621 is 1267997.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5340721 + 2656900 = 2311^2 + 1630^2 .

It is a cyclic number.

It is not a de Polignac number, because 7997621 - 2⁶ = 7997557 is a prime.

Together with 7997623, 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 (7997623) 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, 3998810 + 3998811.

It is an arithmetic number, because the mean of its divisors is an integer number (3998811).

Almost surely, 2^7997621 is an apocalyptic number.

It is an amenable number.

7997621 is a deficient number, since it is larger than the sum of its proper divisors (1).

7997621 is an equidigital number, since it uses as much as digits as its factorization.

7997621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47628, while the sum is 41.

The square root of 7997621 is about 2828.0065417180. The cubic root of 7997621 is about 199.9801730345.

It can be divided in two parts, 79976 and 21, that added together give a palindrome (79997).

The spelling of 7997621 in words is "seven million, nine hundred ninety-seven thousand, six hundred twenty-one".