1243666165 has 16 divisors (see below), whose sum is σ = 1706181120. Its totient is φ = 852508800.

The previous prime is 1243666141. The next prime is 1243666181. The reversal of 1243666165 is 5616663421.

It is not a de Polignac number, because 1243666165 - 2¹⁵ = 1243633397 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 170340 + ... + 177490.

It is an arithmetic number, because the mean of its divisors is an integer number (106636320).

Almost surely, 2^1243666165 is an apocalyptic number.

It is an amenable number.

1243666165 is a deficient number, since it is larger than the sum of its proper divisors (462514955).

1243666165 is an equidigital number, since it uses as much as digits as its factorization.

1243666165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12132.

The product of its digits is 155520, while the sum is 40.

The square root of 1243666165 is about 35265.6513480185. The cubic root of 1243666165 is about 1075.3948187401.

The spelling of 1243666165 in words is "one billion, two hundred forty-three million, six hundred sixty-six thousand, one hundred sixty-five".