2161928931840 has 1280 divisors, whose sum is σ = 8241175388160. Its totient is φ = 542744395776.

The previous prime is 2161928931823. The next prime is 2161928931889. The reversal of 2161928931840 is 481398291612.

It is a happy number.

2161928931840 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 9 + 289 + 318 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1280).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 13263367599 + ... + 13263367761.

It is an arithmetic number, because the mean of its divisors is an integer number (6438418272).

Almost surely, 2^{2161928931840} is an apocalyptic number.

2161928931840 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 2161928931840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4120587694080).

2161928931840 is an abundant number, since it is smaller than the sum of its proper divisors (6079246456320).

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

2161928931840 is an equidigital number, since it uses as much as digits as its factorization.

2161928931840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333 (or 299 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 54.

The spelling of 2161928931840 in words is "two trillion, one hundred sixty-one billion, nine hundred twenty-eight million, nine hundred thirty-one thousand, eight hundred forty".