2117984352561 has 48 divisors (see below), whose sum is σ = 3895358957568. Its totient is φ = 1076841986400.

The previous prime is 2117984352557. The next prime is 2117984352563. The reversal of 2117984352561 is 1652534897112.

2117984352561 is a `hidden beast` number, since 2 + 1 + 1 + 79 + 8 + 4 + 3 + 5 + 2 + 561 = 666.

It is not a de Polignac number, because 2117984352561 - 2² = 2117984352557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2117984352498 and 2117984352507.

It is not an unprimeable number, because it can be changed into a prime (2117984352563) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32480775 + ... + 32545916.

It is an arithmetic number, because the mean of its divisors is an integer number (81153311616).

Almost surely, 2^{2117984352561} is an apocalyptic number.

2117984352561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2117984352561 is a deficient number, since it is larger than the sum of its proper divisors (1777374605007).

2117984352561 is a wasteful number, since it uses less digits than its factorization.

2117984352561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65026762 (or 65026759 counting only the distinct ones).

The product of its digits is 3628800, while the sum is 54.

The spelling of 2117984352561 in words is "two trillion, one hundred seventeen billion, nine hundred eighty-four million, three hundred fifty-two thousand, five hundred sixty-one".