642559971 has 8 divisors (see below), whose sum is σ = 884383744. Its totient is φ = 414554760.

The previous prime is 642559937. The next prime is 642559987. The reversal of 642559971 is 179955246.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 642559971 - 2⁷ = 642559843 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 642559971.

It is not an unprimeable number, because it can be changed into a prime (642559991) 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 7 ways as a sum of consecutive naturals, for example, 3454531 + ... + 3454716.

It is an arithmetic number, because the mean of its divisors is an integer number (110547968).

Almost surely, 2^642559971 is an apocalyptic number.

642559971 is a deficient number, since it is larger than the sum of its proper divisors (241823773).

642559971 is a wasteful number, since it uses less digits than its factorization.

642559971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6909281.

The product of its digits is 680400, while the sum is 48.

The square root of 642559971 is about 25348.7666563878. The cubic root of 642559971 is about 862.9213662187.

The spelling of 642559971 in words is "six hundred forty-two million, five hundred fifty-nine thousand, nine hundred seventy-one".