626660591 has 2 divisors, whose sum is σ = 626660592. Its totient is φ = 626660590.

The previous prime is 626660569. The next prime is 626660609. The reversal of 626660591 is 195066626.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 626660591 - 2¹⁰ = 626659567 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (626660521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 313330295 + 313330296.

It is an arithmetic number, because the mean of its divisors is an integer number (313330296).

Almost surely, 2^626660591 is an apocalyptic number.

626660591 is a deficient number, since it is larger than the sum of its proper divisors (1).

626660591 is an equidigital number, since it uses as much as digits as its factorization.

626660591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 626660591 is about 25033.1897887584. The cubic root of 626660591 is about 855.7445225413.

The spelling of 626660591 in words is "six hundred twenty-six million, six hundred sixty thousand, five hundred ninety-one".