1221420340140 has 1536 divisors, whose sum is σ = 5091699916800. Its totient is φ = 210286264320.

The previous prime is 1221420340097. The next prime is 1221420340141. The reversal of 1221420340140 is 410430241221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221420340140.

It is not an unprimeable number, because it can be changed into a prime (1221420340141) by changing a digit.

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 511 ways as a sum of consecutive naturals, for example, 4540595926 + ... + 4540596194.

It is an arithmetic number, because the mean of its divisors is an integer number (3314908800).

Almost surely, 2^{1221420340140} is an apocalyptic number.

1221420340140 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 1221420340140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2545849958400).

1221420340140 is an abundant number, since it is smaller than the sum of its proper divisors (3870279576660).

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

1221420340140 is a wasteful number, since it uses less digits than its factorization.

1221420340140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527 (or 525 counting only the distinct ones).

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

Adding to 1221420340140 its reverse (410430241221), we get a palindrome (1631850581361).

The spelling of 1221420340140 in words is "one trillion, two hundred twenty-one billion, four hundred twenty million, three hundred forty thousand, one hundred forty".