1221200131340 has 72 divisors (see below), whose sum is σ = 2984889282480. Its totient is φ = 418462547328.

The previous prime is 1221200131259. The next prime is 1221200131343. The reversal of 1221200131340 is 431310021221.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (1221200131343) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1404947 + ... + 2101493.

It is an arithmetic number, because the mean of its divisors is an integer number (41456795590).

Almost surely, 2^{1221200131340} is an apocalyptic number.

1221200131340 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 1221200131340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1492444641240).

1221200131340 is an abundant number, since it is smaller than the sum of its proper divisors (1763689151140).

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

1221200131340 is a wasteful number, since it uses less digits than its factorization.

1221200131340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698359 (or 698350 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 1221200131340 its reverse (431310021221), we get a palindrome (1652510152561).

The spelling of 1221200131340 in words is "one trillion, two hundred twenty-one billion, two hundred million, one hundred thirty-one thousand, three hundred forty".