121221304440 has 32 divisors (see below), whose sum is σ = 363663913680. Its totient is φ = 32325681152.

The previous prime is 121221304363. The next prime is 121221304441. The reversal of 121221304440 is 44403122121.

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

It is a self number, because there is not a number n which added to its sum of digits gives 121221304440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221304441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 505088649 + ... + 505088888.

Almost surely, 2^121221304440 is an apocalyptic number.

121221304440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121221304440 is an abundant number, since it is smaller than the sum of its proper divisors (242442609240).

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

121221304440 is a wasteful number, since it uses less digits than its factorization.

121221304440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1010177551 (or 1010177547 counting only the distinct ones).

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

Adding to 121221304440 its reverse (44403122121), we get a palindrome (165624426561).

The spelling of 121221304440 in words is "one hundred twenty-one billion, two hundred twenty-one million, three hundred four thousand, four hundred forty".