12121305 has 32 divisors (see below), whose sum is σ = 22508544. Its totient is φ = 5455296.

The previous prime is 12121303. The next prime is 12121309. The reversal of 12121305 is 50312121.

It is not a de Polignac number, because 12121305 - 2¹ = 12121303 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12121301) 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, 6174 + ... + 7896.

It is an arithmetic number, because the mean of its divisors is an integer number (703392).

Almost surely, 2^12121305 is an apocalyptic number.

12121305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12121305 is a deficient number, since it is larger than the sum of its proper divisors (10387239).

12121305 is a wasteful number, since it uses less digits than its factorization.

12121305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1805.

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 12121305 is about 3481.5664577888. The cubic root of 12121305 is about 229.7117055799.

Adding to 12121305 its reverse (50312121), we get a palindrome (62433426).

The spelling of 12121305 in words is "twelve million, one hundred twenty-one thousand, three hundred five".