7991897 has 2 divisors, whose sum is σ = 7991898. Its totient is φ = 7991896.

The previous prime is 7991891. The next prime is 7991939. The reversal of 7991897 is 7981997.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7958041 + 33856 = 2821^2 + 184^2 .

It is a cyclic number.

It is not a de Polignac number, because 7991897 - 2¹⁸ = 7729753 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7991891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3995948 + 3995949.

It is an arithmetic number, because the mean of its divisors is an integer number (3995949).

Almost surely, 2^7991897 is an apocalyptic number.

It is an amenable number.

7991897 is a deficient number, since it is larger than the sum of its proper divisors (1).

7991897 is an equidigital number, since it uses as much as digits as its factorization.

7991897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 285768, while the sum is 50.

The square root of 7991897 is about 2826.9943402844. The cubic root of 7991897 is about 199.9324521890.

It can be divided in two parts, 7991 and 897, that added together give a palindrome (8888).

The spelling of 7991897 in words is "seven million, nine hundred ninety-one thousand, eight hundred ninety-seven".