211400081 has 2 divisors, whose sum is σ = 211400082. Its totient is φ = 211400080.

The previous prime is 211400027. The next prime is 211400113. The reversal of 211400081 is 180004112.

211400081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189310081 + 22090000 = 13759^2 + 4700^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211400081 is a prime.

It is a super-2 number, since 2×211400081² = 89379988493613122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211400281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105700040 + 105700041.

It is an arithmetic number, because the mean of its divisors is an integer number (105700041).

Almost surely, 2^211400081 is an apocalyptic number.

It is an amenable number.

211400081 is a deficient number, since it is larger than the sum of its proper divisors (1).

211400081 is an equidigital number, since it uses as much as digits as its factorization.

211400081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 211400081 is about 14539.6038804364. The cubic root of 211400081 is about 595.7102184586.

Adding to 211400081 its reverse (180004112), we get a palindrome (391404193).

The spelling of 211400081 in words is "two hundred eleven million, four hundred thousand, eighty-one".