211681633 has 2 divisors, whose sum is σ = 211681634. Its totient is φ = 211681632.

The previous prime is 211681619. The next prime is 211681661. The reversal of 211681633 is 336186112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 161086864 + 50594769 = 12692^2 + 7113^2 .

It is a cyclic number.

It is not a de Polignac number, because 211681633 - 2¹⁷ = 211550561 is a prime.

It is a super-2 number, since 2×211681633² = 89618227499093378, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211681595 and 211681604.

It is not a weakly prime, because it can be changed into another prime (211681133) 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, 105840816 + 105840817.

It is an arithmetic number, because the mean of its divisors is an integer number (105840817).

Almost surely, 2^211681633 is an apocalyptic number.

It is an amenable number.

211681633 is a deficient number, since it is larger than the sum of its proper divisors (1).

211681633 is an equidigital number, since it uses as much as digits as its factorization.

211681633 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 31.

The square root of 211681633 is about 14549.2829032911. The cubic root of 211681633 is about 595.9745655632.

It can be divided in two parts, 21168 and 1633, that added together give a square (22801 = 151²).

The spelling of 211681633 in words is "two hundred eleven million, six hundred eighty-one thousand, six hundred thirty-three".