2121641660340 has 144 divisors (see below), whose sum is σ = 6719003561088. Its totient is φ = 540886570752.

The previous prime is 2121641660321. The next prime is 2121641660351. The reversal of 2121641660340 is 430661461212.

2121641660340 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 6 + 4 + 1 + 6 + 603 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2121641660295 and 2121641660304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7760614 + ... + 8029346.

It is an arithmetic number, because the mean of its divisors is an integer number (46659746952).

Almost surely, 2^{2121641660340} is an apocalyptic number.

2121641660340 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 2121641660340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3359501780544).

2121641660340 is an abundant number, since it is smaller than the sum of its proper divisors (4597361900748).

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

2121641660340 is a wasteful number, since it uses less digits than its factorization.

2121641660340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270678 (or 270673 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The spelling of 2121641660340 in words is "two trillion, one hundred twenty-one billion, six hundred forty-one million, six hundred sixty thousand, three hundred forty".