618368641661 has 8 divisors (see below), whose sum is σ = 639716023200. Its totient is φ = 597022881840.

The previous prime is 618368641619. The next prime is 618368641663. The reversal of 618368641661 is 166146863816.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-618368641661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 618368641597 and 618368641606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (618368641663) 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, 397310 + ... + 1180928.

It is an arithmetic number, because the mean of its divisors is an integer number (79964502900).

Almost surely, 2^618368641661 is an apocalyptic number.

It is an amenable number.

618368641661 is a deficient number, since it is larger than the sum of its proper divisors (21347381539).

618368641661 is a wasteful number, since it uses less digits than its factorization.

618368641661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810859.

The product of its digits is 5971968, while the sum is 56.

The spelling of 618368641661 in words is "six hundred eighteen billion, three hundred sixty-eight million, six hundred forty-one thousand, six hundred sixty-one".