642031513 has 2 divisors, whose sum is σ = 642031514. Its totient is φ = 642031512.

The previous prime is 642031459. The next prime is 642031517. The reversal of 642031513 is 315130246.

642031513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 615436864 + 26594649 = 24808^2 + 5157^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642031513 is a prime.

It is not a weakly prime, because it can be changed into another prime (642031517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321015756 + 321015757.

It is an arithmetic number, because the mean of its divisors is an integer number (321015757).

Almost surely, 2^642031513 is an apocalyptic number.

It is an amenable number.

642031513 is a deficient number, since it is larger than the sum of its proper divisors (1).

642031513 is an equidigital number, since it uses as much as digits as its factorization.

642031513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 642031513 is about 25338.3407704609. The cubic root of 642031513 is about 862.6847383600.

Adding to 642031513 its reverse (315130246), we get a palindrome (957161759).

The spelling of 642031513 in words is "six hundred forty-two million, thirty-one thousand, five hundred thirteen".