1640064539 has 2 divisors, whose sum is σ = 1640064540. Its totient is φ = 1640064538.

The previous prime is 1640064533. The next prime is 1640064623. The reversal of 1640064539 is 9354600461.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640064539 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1640064533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820032269 + 820032270.

It is an arithmetic number, because the mean of its divisors is an integer number (820032270).

Almost surely, 2^1640064539 is an apocalyptic number.

1640064539 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640064539 is an equidigital number, since it uses as much as digits as its factorization.

1640064539 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 1640064539 is about 40497.7102932993. The cubic root of 1640064539 is about 1179.2891771297.

The spelling of 1640064539 in words is "one billion, six hundred forty million, sixty-four thousand, five hundred thirty-nine".