2170781907840 has 3456 divisors, whose sum is σ = 10580665305600. Its totient is φ = 415039832064.

The previous prime is 2170781907803. The next prime is 2170781907883. The reversal of 2170781907840 is 487091870712.

It is a tau number, because it is divible by the number of its divisors (3456).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 94381822069 + ... + 94381822091.

It is an arithmetic number, because the mean of its divisors is an integer number (3061535100).

Almost surely, 2^{2170781907840} is an apocalyptic number.

2170781907840 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 2170781907840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5290332652800).

2170781907840 is an abundant number, since it is smaller than the sum of its proper divisors (8409883397760).

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

2170781907840 is an equidigital number, since it uses as much as digits as its factorization.

2170781907840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 1580544, while the sum is 54.

The spelling of 2170781907840 in words is "two trillion, one hundred seventy billion, seven hundred eighty-one million, nine hundred seven thousand, eight hundred forty".