1720388539 has 2 divisors, whose sum is σ = 1720388540. Its totient is φ = 1720388538.

The previous prime is 1720388521. The next prime is 1720388567. The reversal of 1720388539 is 9358830271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1720388539 - 2⁵ = 1720388507 is a prime.

It is not a weakly prime, because it can be changed into another prime (1720388599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860194269 + 860194270.

It is an arithmetic number, because the mean of its divisors is an integer number (860194270).

Almost surely, 2^1720388539 is an apocalyptic number.

1720388539 is a deficient number, since it is larger than the sum of its proper divisors (1).

1720388539 is an equidigital number, since it uses as much as digits as its factorization.

1720388539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 1720388539 is about 41477.5666957453. The cubic root of 1720388539 is about 1198.2354944366.

The spelling of 1720388539 in words is "one billion, seven hundred twenty million, three hundred eighty-eight thousand, five hundred thirty-nine".