1647641665123 has 8 divisors (see below), whose sum is σ = 1700813102976. Its totient is φ = 1594471584000.

The previous prime is 1647641665097. The next prime is 1647641665139. The reversal of 1647641665123 is 3215661467461.

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 1647641665123 - 2⁵ = 1647641665091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1647641665193) 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, 2508465 + ... + 3096397.

It is an arithmetic number, because the mean of its divisors is an integer number (212601637872).

Almost surely, 2^{1647641665123} is an apocalyptic number.

1647641665123 is a deficient number, since it is larger than the sum of its proper divisors (53171437853).

1647641665123 is an equidigital number, since it uses as much as digits as its factorization.

1647641665123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678365.

The product of its digits is 4354560, while the sum is 52.

The spelling of 1647641665123 in words is "one trillion, six hundred forty-seven billion, six hundred forty-one million, six hundred sixty-five thousand, one hundred twenty-three".