666020424644 has 6 divisors (see below), whose sum is σ = 1165535743134. Its totient is φ = 333010212320.

The previous prime is 666020424611. The next prime is 666020424701. The reversal of 666020424644 is 446424020666.

It can be written as a sum of positive squares in only one way, i.e., 618991297600 + 47029127044 = 786760^2 + 216862^2 .

It is a junction number, because it is equal to n+sod(n) for n = 666020424595 and 666020424604.

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 as a sum of consecutive naturals, namely, 83252553077 + ... + 83252553084.

It is an arithmetic number, because the mean of its divisors is an integer number (194255957189).

Almost surely, 2^666020424644 is an apocalyptic number.

It is an amenable number.

666020424644 is a deficient number, since it is larger than the sum of its proper divisors (499515318490).

666020424644 is a wasteful number, since it uses less digits than its factorization.

666020424644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166505106165 (or 166505106163 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 44.

The spelling of 666020424644 in words is "six hundred sixty-six billion, twenty million, four hundred twenty-four thousand, six hundred forty-four".