642645339 has 24 divisors (see below), whose sum is σ = 1055392848. Its totient is φ = 345623040.

The previous prime is 642645313. The next prime is 642645343. The reversal of 642645339 is 933546246.

It is not a de Polignac number, because 642645339 - 2¹¹ = 642643291 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642645339.

It is not an unprimeable number, because it can be changed into a prime (642645359) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 126082 + ... + 131079.

It is an arithmetic number, because the mean of its divisors is an integer number (43974702).

Almost surely, 2^642645339 is an apocalyptic number.

642645339 is a deficient number, since it is larger than the sum of its proper divisors (412747509).

642645339 is a wasteful number, since it uses less digits than its factorization.

642645339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257195 (or 257188 counting only the distinct ones).

The product of its digits is 466560, while the sum is 42.

The square root of 642645339 is about 25350.4504693704. The cubic root of 642645339 is about 862.9595793103.

The spelling of 642645339 in words is "six hundred forty-two million, six hundred forty-five thousand, three hundred thirty-nine".