11662544021665 has 4 divisors (see below), whose sum is σ = 13995052826004. Its totient is φ = 9330035217328.

The previous prime is 11662544021647. The next prime is 11662544021669. The reversal of 11662544021665 is 56612044526611.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1773582034081 + 9888961987584 = 1331759^2 + 3144672^2 .

It is a cyclic number.

It is not a de Polignac number, because 11662544021665 - 2²⁹ = 11662007150753 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 not an unprimeable number, because it can be changed into a prime (11662544021669) 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, 1166254402162 + ... + 1166254402171.

It is an arithmetic number, because the mean of its divisors is an integer number (3498763206501).

Almost surely, 2^{11662544021665} is an apocalyptic number.

It is an amenable number.

11662544021665 is a deficient number, since it is larger than the sum of its proper divisors (2332508804339).

11662544021665 is an equidigital number, since it uses as much as digits as its factorization.

11662544021665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2332508804338.

The product of its (nonzero) digits is 2073600, while the sum is 49.

The spelling of 11662544021665 in words is "eleven trillion, six hundred sixty-two billion, five hundred forty-four million, twenty-one thousand, six hundred sixty-five".