666777344441 has 8 divisors (see below), whose sum is σ = 718771222344. Its totient is φ = 614883939840.

The previous prime is 666777344437. The next prime is 666777344447. The reversal of 666777344441 is 144443777666.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 14809916416 + 651967428025 = 121696^2 + 807445^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 666777344441 - 2² = 666777344437 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666777344447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25104536 + ... + 25131081.

It is an arithmetic number, because the mean of its divisors is an integer number (89846402793).

Almost surely, 2^666777344441 is an apocalyptic number.

It is an amenable number.

666777344441 is a deficient number, since it is larger than the sum of its proper divisors (51993877903).

666777344441 is a wasteful number, since it uses less digits than its factorization.

666777344441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50236651.

The product of its digits is 56899584, while the sum is 59.

The spelling of 666777344441 in words is "six hundred sixty-six billion, seven hundred seventy-seven million, three hundred forty-four thousand, four hundred forty-one".