7991275477 has 2 divisors, whose sum is σ = 7991275478. Its totient is φ = 7991275476.

The previous prime is 7991275427. The next prime is 7991275489. The reversal of 7991275477 is 7745721997.

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., 7989856996 + 1418481 = 89386^2 + 1191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7991275477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7991275427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3995637738 + 3995637739.

It is an arithmetic number, because the mean of its divisors is an integer number (3995637739).

Almost surely, 2^7991275477 is an apocalyptic number.

It is an amenable number.

7991275477 is a deficient number, since it is larger than the sum of its proper divisors (1).

7991275477 is an equidigital number, since it uses as much as digits as its factorization.

7991275477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7779240, while the sum is 58.

The square root of 7991275477 is about 89393.9342293424. The cubic root of 7991275477 is about 1999.2726919602.

The spelling of 7991275477 in words is "seven billion, nine hundred ninety-one million, two hundred seventy-five thousand, four hundred seventy-seven".