211212137 has 2 divisors, whose sum is σ = 211212138. Its totient is φ = 211212136.

The previous prime is 211212121. The next prime is 211212143. The reversal of 211212137 is 731212112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142587481 + 68624656 = 11941^2 + 8284^2 .

It is a cyclic number.

It is not a de Polignac number, because 211212137 - 2⁴ = 211212121 is a prime.

It is a super-2 number, since 2×211212137² = 89221133632213538, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (211202137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105606068 + 105606069.

It is an arithmetic number, because the mean of its divisors is an integer number (105606069).

Almost surely, 2^211212137 is an apocalyptic number.

It is an amenable number.

211212137 is a deficient number, since it is larger than the sum of its proper divisors (1).

211212137 is an equidigital number, since it uses as much as digits as its factorization.

211212137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 20.

The square root of 211212137 is about 14533.1392685820. The cubic root of 211212137 is about 595.5336285596.

Adding to 211212137 its reverse (731212112), we get a palindrome (942424249).

The spelling of 211212137 in words is "two hundred eleven million, two hundred twelve thousand, one hundred thirty-seven".