11817987362409 has 4 divisors (see below), whose sum is σ = 15757316483216. Its totient is φ = 7878658241604.

The previous prime is 11817987362399. The next prime is 11817987362411. The reversal of 11817987362409 is 90426378971811.

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 not a de Polignac number, because 11817987362409 - 2²⁵ = 11817953807977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11817987362409.

It is not an unprimeable number, because it can be changed into a prime (11817987362309) 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, 1969664560399 + ... + 1969664560404.

It is an arithmetic number, because the mean of its divisors is an integer number (3939329120804).

Almost surely, 2^{11817987362409} is an apocalyptic number.

It is an amenable number.

11817987362409 is a deficient number, since it is larger than the sum of its proper divisors (3939329120807).

11817987362409 is an equidigital number, since it uses as much as digits as its factorization.

11817987362409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3939329120806.

The product of its (nonzero) digits is 36578304, while the sum is 66.

The spelling of 11817987362409 in words is "eleven trillion, eight hundred seventeen billion, nine hundred eighty-seven million, three hundred sixty-two thousand, four hundred nine".