12121221400 has 24 divisors (see below), whose sum is σ = 28181840220. Its totient is φ = 4848488480.

The previous prime is 12121221337. The next prime is 12121221407. The reversal of 12121221400 is 412212121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121221407) 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, 30302854 + ... + 30303253.

Almost surely, 2^12121221400 is an apocalyptic number.

12121221400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121221400 is an abundant number, since it is smaller than the sum of its proper divisors (16060618820).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12121221400 is a wasteful number, since it uses less digits than its factorization.

12121221400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60606123 (or 60606114 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 12121221400 its reverse (412212121), we get a palindrome (12533433521).

The spelling of 12121221400 in words is "twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, four hundred".