2161620156344 has 128 divisors (see below), whose sum is σ = 4486045006080. Its totient is φ = 968340172800.

The previous prime is 2161620156343. The next prime is 2161620156373. The reversal of 2161620156344 is 4436510261612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161620156343) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1151634734 + ... + 1151636610.

It is an arithmetic number, because the mean of its divisors is an integer number (35047226610).

Almost surely, 2^{2161620156344} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2161620156344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2243022503040).

2161620156344 is an abundant number, since it is smaller than the sum of its proper divisors (2324424849736).

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

2161620156344 is a wasteful number, since it uses less digits than its factorization.

2161620156344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2661 (or 2657 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 2161620156344 in words is "two trillion, one hundred sixty-one billion, six hundred twenty million, one hundred fifty-six thousand, three hundred forty-four".