12121356825 has 36 divisors (see below), whose sum is σ = 21840768768. Its totient is φ = 6425992800.

The previous prime is 12121356811. The next prime is 12121356827. The reversal of 12121356825 is 52865312121.

It is not a de Polignac number, because 12121356825 - 2¹² = 12121352729 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12121356825.

It is not an unprimeable number, because it can be changed into a prime (12121356827) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 123721 + ... + 198870.

Almost surely, 2^12121356825 is an apocalyptic number.

12121356825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12121356825 is a deficient number, since it is larger than the sum of its proper divisors (9719411943).

12121356825 is a wasteful number, since it uses less digits than its factorization.

12121356825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322774 (or 322766 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

Adding to 12121356825 its reverse (52865312121), we get a palindrome (64986668946).

The spelling of 12121356825 in words is "twelve billion, one hundred twenty-one million, three hundred fifty-six thousand, eight hundred twenty-five".