642165863 has 2 divisors, whose sum is σ = 642165864. Its totient is φ = 642165862.

The previous prime is 642165847. The next prime is 642165893. The reversal of 642165863 is 368561246.

642165863 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 642165863 - 2⁴ = 642165847 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642165863.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642165833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321082931 + 321082932.

It is an arithmetic number, because the mean of its divisors is an integer number (321082932).

Almost surely, 2^642165863 is an apocalyptic number.

642165863 is a deficient number, since it is larger than the sum of its proper divisors (1).

642165863 is an equidigital number, since it uses as much as digits as its factorization.

642165863 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 41.

The square root of 642165863 is about 25340.9917524946. The cubic root of 642165863 is about 862.7449086210.

The spelling of 642165863 in words is "six hundred forty-two million, one hundred sixty-five thousand, eight hundred sixty-three".