665541593837 has 4 divisors (see below), whose sum is σ = 665549170560. Its totient is φ = 665534017116.

The previous prime is 665541593833. The next prime is 665541593887. The reversal of 665541593837 is 738395145566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 665541593837 - 2² = 665541593833 is a prime.

It is a super-2 number, since 2×665541593837² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 665541593837.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665541593833) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3655037 + ... + 3832802.

It is an arithmetic number, because the mean of its divisors is an integer number (166387292640).

Almost surely, 2^665541593837 is an apocalyptic number.

It is an amenable number.

665541593837 is a deficient number, since it is larger than the sum of its proper divisors (7576723).

665541593837 is an equidigital number, since it uses as much as digits as its factorization.

665541593837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7576722.

The product of its digits is 81648000, while the sum is 62.

The spelling of 665541593837 in words is "six hundred sixty-five billion, five hundred forty-one million, five hundred ninety-three thousand, eight hundred thirty-seven".