642880479 has 4 divisors (see below), whose sum is σ = 857173976. Its totient is φ = 428586984.

The previous prime is 642880471. The next prime is 642880489. The reversal of 642880479 is 974088246.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 642880479 - 2³ = 642880471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642880471) 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 in 3 ways as a sum of consecutive naturals, for example, 107146744 + ... + 107146749.

It is an arithmetic number, because the mean of its divisors is an integer number (214293494).

Almost surely, 2^642880479 is an apocalyptic number.

642880479 is a deficient number, since it is larger than the sum of its proper divisors (214293497).

642880479 is a wasteful number, since it uses less digits than its factorization.

642880479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214293496.

The product of its (nonzero) digits is 774144, while the sum is 48.

The square root of 642880479 is about 25355.0878326225. The cubic root of 642880479 is about 863.0648170205.

The spelling of 642880479 in words is "six hundred forty-two million, eight hundred eighty thousand, four hundred seventy-nine".