1640065591 has 2 divisors, whose sum is σ = 1640065592. Its totient is φ = 1640065590.

The previous prime is 1640065529. The next prime is 1640065619. The reversal of 1640065591 is 1955600461.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1640065591 - 2⁹ = 1640065079 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1640065591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1640062591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820032795 + 820032796.

It is an arithmetic number, because the mean of its divisors is an integer number (820032796).

Almost surely, 2^1640065591 is an apocalyptic number.

1640065591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640065591 is an equidigital number, since it uses as much as digits as its factorization.

1640065591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 1640065591 is about 40497.7232816858. The cubic root of 1640065591 is about 1179.2894292767.

The spelling of 1640065591 in words is "one billion, six hundred forty million, sixty-five thousand, five hundred ninety-one".