2161361440 has 96 divisors (see below), whose sum is σ = 5901517440. Its totient is φ = 732678144.

The previous prime is 2161361437. The next prime is 2161361467. The reversal of 2161361440 is 441631612.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 2161361399 and 2161361408.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88839 + ... + 110521.

It is an arithmetic number, because the mean of its divisors is an integer number (61474140).

Almost surely, 2^2161361440 is an apocalyptic number.

2161361440 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 2161361440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2950758720).

2161361440 is an abundant number, since it is smaller than the sum of its proper divisors (3740156000).

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

2161361440 is a wasteful number, since it uses less digits than its factorization.

2161361440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21794 (or 21786 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 2161361440 is about 46490.4446096184. Note that the first 3 decimals coincide. The cubic root of 2161361440 is about 1292.9323434203.

The spelling of 2161361440 in words is "two billion, one hundred sixty-one million, three hundred sixty-one thousand, four hundred forty".