642005420 has 48 divisors (see below), whose sum is σ = 1542336768. Its totient is φ = 219898560.

The previous prime is 642005407. The next prime is 642005449. The reversal of 642005420 is 24500246.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 211715 + ... + 214725.

It is an arithmetic number, because the mean of its divisors is an integer number (32132016).

Almost surely, 2^642005420 is an apocalyptic number.

It is an amenable number.

642005420 is an abundant number, since it is smaller than the sum of its proper divisors (900331348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642005420 is a wasteful number, since it uses less digits than its factorization.

642005420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4550 (or 4548 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 642005420 is about 25337.8258735828. The cubic root of 642005420 is about 862.6730513231.

Adding to 642005420 its reverse (24500246), we get a palindrome (666505666).

The spelling of 642005420 in words is "six hundred forty-two million, five thousand, four hundred twenty".