2161444446720 has 960 divisors, whose sum is σ = 8242358892768. Its totient is φ = 520224768000.

The previous prime is 2161444446719. The next prime is 2161444446727. The reversal of 2161444446720 is 276444441612.

2161444446720 is a `hidden beast` number, since 2 + 1 + 6 + 144 + 44 + 467 + 2 + 0 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 398837719296 + 1762606727424 = 631536^2 + 1327632^2 .

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (2161444446727) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5134072110 + ... + 5134072530.

Almost surely, 2^{2161444446720} is an apocalyptic number.

2161444446720 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 2161444446720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4121179446384).

2161444446720 is an abundant number, since it is smaller than the sum of its proper divisors (6080914446048).

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

2161444446720 is a wasteful number, since it uses less digits than its factorization.

2161444446720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805 (or 786 counting only the distinct ones).

The product of its (nonzero) digits is 1032192, while the sum is 45.

The spelling of 2161444446720 in words is "two trillion, one hundred sixty-one billion, four hundred forty-four million, four hundred forty-six thousand, seven hundred twenty".