2181959782485 has 64 divisors (see below), whose sum is σ = 4131992223744. Its totient is φ = 962146252800.

The previous prime is 2181959782411. The next prime is 2181959782489. The reversal of 2181959782485 is 5842879591812.

It is not a de Polignac number, because 2181959782485 - 2⁹ = 2181959781973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181959782489) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 92476 + ... + 2091045.

It is an arithmetic number, because the mean of its divisors is an integer number (64562378496).

Almost surely, 2^{2181959782485} is an apocalyptic number.

It is an amenable number.

2181959782485 is a deficient number, since it is larger than the sum of its proper divisors (1950032441259).

2181959782485 is a wasteful number, since it uses less digits than its factorization.

2181959782485 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2183874.

The product of its digits is 116121600, while the sum is 69.

The spelling of 2181959782485 in words is "two trillion, one hundred eighty-one billion, nine hundred fifty-nine million, seven hundred eighty-two thousand, four hundred eighty-five".