665672126813 has 8 divisors (see below), whose sum is σ = 669680782848. Its totient is φ = 661669830864.

The previous prime is 665672126807. The next prime is 665672126863. The reversal of 665672126813 is 318621276566.

It is a happy number.

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 665672126813 - 2¹⁴ = 665672110429 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 (665672126863) 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, 1379981 + ... + 1798802.

It is an arithmetic number, because the mean of its divisors is an integer number (83710097856).

Almost surely, 2^665672126813 is an apocalyptic number.

It is an amenable number.

665672126813 is a deficient number, since it is larger than the sum of its proper divisors (4008656035).

665672126813 is a wasteful number, since it uses less digits than its factorization.

665672126813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3180043.

The product of its digits is 4354560, while the sum is 53.

The spelling of 665672126813 in words is "six hundred sixty-five billion, six hundred seventy-two million, one hundred twenty-six thousand, eight hundred thirteen".