642505229 has 2 divisors, whose sum is σ = 642505230. Its totient is φ = 642505228.

The previous prime is 642505217. The next prime is 642505247. The reversal of 642505229 is 922505246.

642505229 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 can be written as a sum of positive squares in only one way, i.e., 561595204 + 80910025 = 23698^2 + 8995^2 .

It is a cyclic number.

It is not a de Polignac number, because 642505229 - 2²⁰ = 641456653 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642505249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321252614 + 321252615.

It is an arithmetic number, because the mean of its divisors is an integer number (321252615).

Almost surely, 2^642505229 is an apocalyptic number.

It is an amenable number.

642505229 is a deficient number, since it is larger than the sum of its proper divisors (1).

642505229 is an equidigital number, since it uses as much as digits as its factorization.

642505229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 642505229 is about 25347.6868569895. The cubic root of 642505229 is about 862.8968603956.

The spelling of 642505229 in words is "six hundred forty-two million, five hundred five thousand, two hundred twenty-nine".