666195749213 has 8 divisors (see below), whose sum is σ = 670436226936. Its totient is φ = 661959750400.

The previous prime is 666195749183. The next prime is 666195749231. The reversal of 666195749213 is 312947591666.

It can be written as a sum of positive squares in 4 ways, for example, as 182173605124 + 484022144089 = 426818^2 + 695717^2 .

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 666195749213 - 2²² = 666191554909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666195779213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 821048 + ... + 1416513.

It is an arithmetic number, because the mean of its divisors is an integer number (83804528367).

Almost surely, 2^666195749213 is an apocalyptic number.

It is an amenable number.

666195749213 is a deficient number, since it is larger than the sum of its proper divisors (4240477723).

666195749213 is a wasteful number, since it uses less digits than its factorization.

666195749213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2239455.

The product of its digits is 14696640, while the sum is 59.

The spelling of 666195749213 in words is "six hundred sixty-six billion, one hundred ninety-five million, seven hundred forty-nine thousand, two hundred thirteen".