12121200105 has 32 divisors (see below), whose sum is σ = 22879469568. Its totient is φ = 5362372800.

The previous prime is 12121200103. The next prime is 12121200121. The reversal of 12121200105 is 50100212121.

It is not a de Polignac number, because 12121200105 - 2¹ = 12121200103 is a prime.

It is a super-2 number, since 2×12121200105² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (12121200103) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1858681 + ... + 1865190.

It is an arithmetic number, because the mean of its divisors is an integer number (714983424).

Almost surely, 2^12121200105 is an apocalyptic number.

12121200105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12121200105 is a deficient number, since it is larger than the sum of its proper divisors (10758269463).

12121200105 is a wasteful number, since it uses less digits than its factorization.

12121200105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3723917.

The product of its (nonzero) digits is 40, while the sum is 15.

Adding to 12121200105 its reverse (50100212121), we get a palindrome (62221412226).

It can be divided in two parts, 12121 and 200105, that added together give a triangular number (212226 = T₆₅₁).

The spelling of 12121200105 in words is "twelve billion, one hundred twenty-one million, two hundred thousand, one hundred five".