642919523 has 2 divisors, whose sum is σ = 642919524. Its totient is φ = 642919522.

The previous prime is 642919507. The next prime is 642919559. The reversal of 642919523 is 325919246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 642919523 - 2⁴ = 642919507 is a prime.

It is not a weakly prime, because it can be changed into another prime (642919223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321459761 + 321459762.

It is an arithmetic number, because the mean of its divisors is an integer number (321459762).

Almost surely, 2^642919523 is an apocalyptic number.

642919523 is a deficient number, since it is larger than the sum of its proper divisors (1).

642919523 is an equidigital number, since it uses as much as digits as its factorization.

642919523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 41.

The square root of 642919523 is about 25355.8577650215. The cubic root of 642919523 is about 863.0822888118.

It can be divided in two parts, 6429 and 19523, that added together give a palindrome (25952).

The spelling of 642919523 in words is "six hundred forty-two million, nine hundred nineteen thousand, five hundred twenty-three".