665719853761 has 8 divisors (see below), whose sum is σ = 667669663584. Its totient is φ = 663770405760.

The previous prime is 665719853719. The next prime is 665719853801. The reversal of 665719853761 is 167358917566.

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 665719853761 - 2¹³ = 665719845569 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665719853693 and 665719853702.

It is not an unprimeable number, because it can be changed into a prime (665719553761) 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, 3844530 + ... + 4013956.

It is an arithmetic number, because the mean of its divisors is an integer number (83458707948).

Almost surely, 2^665719853761 is an apocalyptic number.

It is an amenable number.

665719853761 is a deficient number, since it is larger than the sum of its proper divisors (1949809823).

665719853761 is a wasteful number, since it uses less digits than its factorization.

665719853761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180911.

The product of its digits is 57153600, while the sum is 64.

The spelling of 665719853761 in words is "six hundred sixty-five billion, seven hundred nineteen million, eight hundred fifty-three thousand, seven hundred sixty-one".