212820137 has 2 divisors, whose sum is σ = 212820138. Its totient is φ = 212820136.

The previous prime is 212820133. The next prime is 212820149. The reversal of 212820137 is 731028212.

212820137 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 194295721 + 18524416 = 13939^2 + 4304^2 .

It is a cyclic number.

It is not a de Polignac number, because 212820137 - 2² = 212820133 is a prime.

It is not a weakly prime, because it can be changed into another prime (212820133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106410068 + 106410069.

It is an arithmetic number, because the mean of its divisors is an integer number (106410069).

Almost surely, 2^212820137 is an apocalyptic number.

It is an amenable number.

212820137 is a deficient number, since it is larger than the sum of its proper divisors (1).

212820137 is an equidigital number, since it uses as much as digits as its factorization.

212820137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 212820137 is about 14588.3562130899. The cubic root of 212820137 is about 597.0411147234.

Adding to 212820137 its reverse (731028212), we get a palindrome (943848349).

The spelling of 212820137 in words is "two hundred twelve million, eight hundred twenty thousand, one hundred thirty-seven".