2121400343420 has 96 divisors (see below), whose sum is σ = 4812932718720. Its totient is φ = 783025689600.

The previous prime is 2121400343389. The next prime is 2121400343501. The reversal of 2121400343420 is 243430041212.

It is a self number, because there is not a number n which added to its sum of digits gives 2121400343420.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16115870 + ... + 16246970.

It is an arithmetic number, because the mean of its divisors is an integer number (50134715820).

Almost surely, 2^{2121400343420} is an apocalyptic number.

2121400343420 is a gapful number since it is divisible by the number (20) 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 2121400343420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2406466359360).

2121400343420 is an abundant number, since it is smaller than the sum of its proper divisors (2691532375300).

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

2121400343420 is a wasteful number, since it uses less digits than its factorization.

2121400343420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132375 (or 132373 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 2121400343420 its reverse (243430041212), we get a palindrome (2364830384632).

The spelling of 2121400343420 in words is "two trillion, one hundred twenty-one billion, four hundred million, three hundred forty-three thousand, four hundred twenty".