642746719 has 2 divisors, whose sum is σ = 642746720. Its totient is φ = 642746718.

The previous prime is 642746711. The next prime is 642746737. The reversal of 642746719 is 917647246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 642746719 - 2³ = 642746711 is a prime.

It is a super-2 number, since 2×642746719² = 826246689570529922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642746711) 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, 321373359 + 321373360.

It is an arithmetic number, because the mean of its divisors is an integer number (321373360).

Almost surely, 2^642746719 is an apocalyptic number.

642746719 is a deficient number, since it is larger than the sum of its proper divisors (1).

642746719 is an equidigital number, since it uses as much as digits as its factorization.

642746719 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 508032, while the sum is 46.

The square root of 642746719 is about 25352.4499605068. The cubic root of 642746719 is about 863.0049554231.

The spelling of 642746719 in words is "six hundred forty-two million, seven hundred forty-six thousand, seven hundred nineteen".