642441255457 has 4 divisors (see below), whose sum is σ = 642533713300. Its totient is φ = 642348797616.

The previous prime is 642441255427. The next prime is 642441255499. The reversal of 642441255457 is 754552144246.

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

It can be written as a sum of positive squares in 2 ways, for example, as 574570064016 + 67871191441 = 758004^2 + 260521^2 .

It is a cyclic number.

It is not a de Polignac number, because 642441255457 - 2¹¹ = 642441253409 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 642441255457.

It is not an unprimeable number, because it can be changed into a prime (642441255427) 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 3 ways as a sum of consecutive naturals, for example, 46218498 + ... + 46232395.

It is an arithmetic number, because the mean of its divisors is an integer number (160633428325).

Almost surely, 2^642441255457 is an apocalyptic number.

It is an amenable number.

642441255457 is a deficient number, since it is larger than the sum of its proper divisors (92457843).

642441255457 is an equidigital number, since it uses as much as digits as its factorization.

642441255457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92457842.

The product of its digits is 5376000, while the sum is 49.

The spelling of 642441255457 in words is "six hundred forty-two billion, four hundred forty-one million, two hundred fifty-five thousand, four hundred fifty-seven".