660026644663 has 4 divisors (see below), whose sum is σ = 660099754440. Its totient is φ = 659953534888.

The previous prime is 660026644661. The next prime is 660026644687. The reversal of 660026644663 is 366446620066.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 660026644663 - 2¹ = 660026644661 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660026644661) 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, 36541345 + ... + 36559402.

It is an arithmetic number, because the mean of its divisors is an integer number (165024938610).

Almost surely, 2^660026644663 is an apocalyptic number.

660026644663 is a deficient number, since it is larger than the sum of its proper divisors (73109777).

660026644663 is an equidigital number, since it uses as much as digits as its factorization.

660026644663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73109776.

The product of its (nonzero) digits is 4478976, while the sum is 49.

The spelling of 660026644663 in words is "six hundred sixty billion, twenty-six million, six hundred forty-four thousand, six hundred sixty-three".