11805138851 has 6 divisors (see below), whose sum is σ = 12975896556. Its totient is φ = 10731944300.

The previous prime is 11805138833. The next prime is 11805138869. The reversal of 11805138851 is 15883150811.

It is an interprime number because it is at equal distance from previous prime (11805138833) and next prime (11805138869).

It is a de Polignac number, because none of the positive numbers 2^k-11805138851 is a prime.

It is a super-2 number, since 2×11805138851² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11805138799 and 11805138808.

It is not an unprimeable number, because it can be changed into a prime (11805138151) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 48781445 + ... + 48781686.

It is an arithmetic number, because the mean of its divisors is an integer number (2162649426).

Almost surely, 2^11805138851 is an apocalyptic number.

11805138851 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11805138851 is a deficient number, since it is larger than the sum of its proper divisors (1170757705).

11805138851 is an equidigital number, since it uses as much as digits as its factorization.

11805138851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97563153 (or 97563142 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 41.

The spelling of 11805138851 in words is "eleven billion, eight hundred five million, one hundred thirty-eight thousand, eight hundred fifty-one".