2156643211 has 2 divisors, whose sum is σ = 2156643212. Its totient is φ = 2156643210.

The previous prime is 2156643191. The next prime is 2156643221. The reversal of 2156643211 is 1123466512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2156643211 is a prime.

It is a super-2 number, since 2×2156643211² = 9302219879104781042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2156643221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078321605 + 1078321606.

It is an arithmetic number, because the mean of its divisors is an integer number (1078321606).

Almost surely, 2^2156643211 is an apocalyptic number.

2156643211 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156643211 is an equidigital number, since it uses as much as digits as its factorization.

2156643211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8640, while the sum is 31.

The square root of 2156643211 is about 46439.6728132316. The cubic root of 2156643211 is about 1291.9908388117.

The spelling of 2156643211 in words is "two billion, one hundred fifty-six million, six hundred forty-three thousand, two hundred eleven".