2161864916980 has 48 divisors (see below), whose sum is σ = 4663563040080. Its totient is φ = 841203698688.

The previous prime is 2161864916957. The next prime is 2161864917089. The reversal of 2161864916980 is 896194681612.

It can be written as a sum of positive squares in 8 ways, for example, as 112002670224 + 2049862246756 = 334668^2 + 1431734^2 .

It is a congruent number.

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, 3383094 + ... + 3971026.

It is an arithmetic number, because the mean of its divisors is an integer number (97157563335).

Almost surely, 2^{2161864916980} is an apocalyptic number.

2161864916980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2161864916980 is an abundant number, since it is smaller than the sum of its proper divisors (2501698123100).

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

2161864916980 is a wasteful number, since it uses less digits than its factorization.

2161864916980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 592948 (or 592946 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 61.

The spelling of 2161864916980 in words is "two trillion, one hundred sixty-one billion, eight hundred sixty-four million, nine hundred sixteen thousand, nine hundred eighty".