642218444450 has 54 divisors (see below), whose sum is σ = 1313119175697. Its totient is φ = 233511313200.

The previous prime is 642218444437. The next prime is 642218444477. The reversal of 642218444450 is 54444812246.

It can be written as a sum of positive squares in 2 ways, for example, as 629374075561 + 12844368889 = 793331^2 + 113333^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=566665.

It is a Duffinian number.

It is an unprimeable number.

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 26 ways as a sum of consecutive naturals, for example, 62327999 + ... + 62338301.

Almost surely, 2^642218444450 is an apocalyptic number.

642218444450 is an abundant number, since it is smaller than the sum of its proper divisors (670900731247).

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

642218444450 is an equidigital number, since it uses as much as digits as its factorization.

642218444450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20640 (or 10321 counting only the distinct ones).

The product of its (nonzero) digits is 983040, while the sum is 44.

The spelling of 642218444450 in words is "six hundred forty-two billion, two hundred eighteen million, four hundred forty-four thousand, four hundred fifty".