1165785890909 has 4 divisors (see below), whose sum is σ = 1216472234016. Its totient is φ = 1115099547804.

The previous prime is 1165785890873. The next prime is 1165785890987. The reversal of 1165785890909 is 9090985875611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1165785890909 - 2¹² = 1165785886813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1165785890989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25343171519 + ... + 25343171564.

It is an arithmetic number, because the mean of its divisors is an integer number (304118058504).

Almost surely, 2^{1165785890909} is an apocalyptic number.

It is an amenable number.

1165785890909 is a deficient number, since it is larger than the sum of its proper divisors (50686343107).

1165785890909 is an equidigital number, since it uses as much as digits as its factorization.

1165785890909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50686343106.

The product of its (nonzero) digits is 48988800, while the sum is 68.

The spelling of 1165785890909 in words is "one trillion, one hundred sixty-five billion, seven hundred eighty-five million, eight hundred ninety thousand, nine hundred nine".