212631217 has 2 divisors, whose sum is σ = 212631218. Its totient is φ = 212631216.

The previous prime is 212631203. The next prime is 212631233. The reversal of 212631217 is 712136212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 210569121 + 2062096 = 14511^2 + 1436^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212631217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212631191 and 212631200.

It is not a weakly prime, because it can be changed into another prime (212634217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106315608 + 106315609.

It is an arithmetic number, because the mean of its divisors is an integer number (106315609).

Almost surely, 2^212631217 is an apocalyptic number.

It is an amenable number.

212631217 is a deficient number, since it is larger than the sum of its proper divisors (1).

212631217 is an equidigital number, since it uses as much as digits as its factorization.

212631217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 25.

The square root of 212631217 is about 14581.8797485098. The cubic root of 212631217 is about 596.8643983644.

Adding to 212631217 its reverse (712136212), we get a palindrome (924767429).

The spelling of 212631217 in words is "two hundred twelve million, six hundred thirty-one thousand, two hundred seventeen".