11865943819 has 2 divisors, whose sum is σ = 11865943820. Its totient is φ = 11865943818.

The previous prime is 11865943807. The next prime is 11865943907. The reversal of 11865943819 is 91834956811.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11865943819 - 2⁵ = 11865943787 is a prime.

It is a super-2 number, since 2×11865943819² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11865943819.

It is not a weakly prime, because it can be changed into another prime (11865913819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5932971909 + 5932971910.

It is an arithmetic number, because the mean of its divisors is an integer number (5932971910).

Almost surely, 2^11865943819 is an apocalyptic number.

11865943819 is a deficient number, since it is larger than the sum of its proper divisors (1).

11865943819 is an equidigital number, since it uses as much as digits as its factorization.

11865943819 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 55.

The spelling of 11865943819 in words is "eleven billion, eight hundred sixty-five million, nine hundred forty-three thousand, eight hundred nineteen".