391216627 has 2 divisors, whose sum is σ = 391216628. Its totient is φ = 391216626.

The previous prime is 391216601. The next prime is 391216643. The reversal of 391216627 is 726612193.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391216627 is a prime.

It is equal to p_20892547 and since 391216627 and 20892547 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (391216667) 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, 195608313 + 195608314.

It is an arithmetic number, because the mean of its divisors is an integer number (195608314).

Almost surely, 2^391216627 is an apocalyptic number.

391216627 is a deficient number, since it is larger than the sum of its proper divisors (1).

391216627 is an equidigital number, since it uses as much as digits as its factorization.

391216627 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 37.

The square root of 391216627 is about 19779.1968239360. The cubic root of 391216627 is about 731.3732996655.

It can be divided in two parts, 3912166 and 27, that added together give a palindrome (3912193).

The spelling of 391216627 in words is "three hundred ninety-one million, two hundred sixteen thousand, six hundred twenty-seven".