12111878821 has 16 divisors (see below), whose sum is σ = 14447351808. Its totient is φ = 9927918000.

The previous prime is 12111878813. The next prime is 12111878827. The reversal of 12111878821 is 12887811121.

It is not a de Polignac number, because 12111878821 - 2³ = 12111878813 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 (12111878827) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1188096 + ... + 1198246.

It is an arithmetic number, because the mean of its divisors is an integer number (902959488).

Almost surely, 2^12111878821 is an apocalyptic number.

It is an amenable number.

12111878821 is a deficient number, since it is larger than the sum of its proper divisors (2335472987).

12111878821 is a wasteful number, since it uses less digits than its factorization.

12111878821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17592.

The product of its digits is 14336, while the sum is 40.

It can be divided in two parts, 121 and 11878821, that multiplied together give a palindrome (1437337341).

The spelling of 12111878821 in words is "twelve billion, one hundred eleven million, eight hundred seventy-eight thousand, eight hundred twenty-one".