2181227263857 has 12 divisors (see below), whose sum is σ = 3151104889140. Its totient is φ = 1453946915808.

The previous prime is 2181227263849. The next prime is 2181227263861. The reversal of 2181227263857 is 7583627221812.

2181227263857 is a `hidden beast` number, since 2 + 1 + 81 + 227 + 263 + 85 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 433215392481 + 1748011871376 = 658191^2 + 1322124^2 .

It is not a de Polignac number, because 2181227263857 - 2³ = 2181227263849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2181227263847) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16981918 + ... + 17109879.

It is an arithmetic number, because the mean of its divisors is an integer number (262592074095).

Almost surely, 2^{2181227263857} is an apocalyptic number.

It is an amenable number.

2181227263857 is a deficient number, since it is larger than the sum of its proper divisors (969877625283).

2181227263857 is a wasteful number, since it uses less digits than its factorization.

2181227263857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34098912 (or 34098909 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 54.

The spelling of 2181227263857 in words is "two trillion, one hundred eighty-one billion, two hundred twenty-seven million, two hundred sixty-three thousand, eight hundred fifty-seven".