642015211 has 2 divisors, whose sum is σ = 642015212. Its totient is φ = 642015210.

The previous prime is 642015203. The next prime is 642015277. The reversal of 642015211 is 112510246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 642015211 - 2³ = 642015203 is a prime.

It is not a weakly prime, because it can be changed into another prime (642015281) 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, 321007605 + 321007606.

It is an arithmetic number, because the mean of its divisors is an integer number (321007606).

Almost surely, 2^642015211 is an apocalyptic number.

642015211 is a deficient number, since it is larger than the sum of its proper divisors (1).

642015211 is an equidigital number, since it uses as much as digits as its factorization.

642015211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 642015211 is about 25338.0190820040. The cubic root of 642015211 is about 862.6774367425.

Adding to 642015211 its reverse (112510246), we get a palindrome (754525457).

The spelling of 642015211 in words is "six hundred forty-two million, fifteen thousand, two hundred eleven".