2181632857 has 2 divisors, whose sum is σ = 2181632858. Its totient is φ = 2181632856.

The previous prime is 2181632809. The next prime is 2181632863. The reversal of 2181632857 is 7582361812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1444836121 + 736796736 = 38011^2 + 27144^2 .

It is a cyclic number.

It is not a de Polignac number, because 2181632857 - 2¹¹ = 2181630809 is a prime.

It is a super-3 number, since 3×2181632857³ (a number of 29 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (2181632867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090816428 + 1090816429.

It is an arithmetic number, because the mean of its divisors is an integer number (1090816429).

Almost surely, 2^2181632857 is an apocalyptic number.

It is an amenable number.

2181632857 is a deficient number, since it is larger than the sum of its proper divisors (1).

2181632857 is an equidigital number, since it uses as much as digits as its factorization.

2181632857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 43.

The square root of 2181632857 is about 46707.9528239036. The cubic root of 2181632857 is about 1296.9619108674.

The spelling of 2181632857 in words is "two billion, one hundred eighty-one million, six hundred thirty-two thousand, eight hundred fifty-seven".