12261440400 has 480 divisors, whose sum is σ = 45902526336. Its totient is φ = 2764800000.

The previous prime is 12261440333. The next prime is 12261440413. The reversal of 12261440400 is 404416221.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 22664130 + ... + 22664670.

Almost surely, 2^12261440400 is an apocalyptic number.

12261440400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12261440400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22951263168).

12261440400 is an abundant number, since it is smaller than the sum of its proper divisors (33641085936).

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

12261440400 is a wasteful number, since it uses less digits than its factorization.

12261440400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691 (or 680 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 12261440400 its reverse (404416221), we get a palindrome (12665856621).

The spelling of 12261440400 in words is "twelve billion, two hundred sixty-one million, four hundred forty thousand, four hundred".