1640539 has 2 divisors, whose sum is σ = 1640540. Its totient is φ = 1640538.

The previous prime is 1640531. The next prime is 1640549. The reversal of 1640539 is 9350461.

It is a weak prime.

It is an emirp because it is prime and its reverse (9350461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1640539 - 2³ = 1640531 is a prime.

It is not a weakly prime, because it can be changed into another prime (1640531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820269 + 820270.

It is an arithmetic number, because the mean of its divisors is an integer number (820270).

2^1640539 is an apocalyptic number.

1640539 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640539 is an equidigital number, since it uses as much as digits as its factorization.

1640539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 1640539 is about 1280.8352743425. The cubic root of 1640539 is about 117.9402886634.

The spelling of 1640539 in words is "one million, six hundred forty thousand, five hundred thirty-nine".