211431247 has 2 divisors, whose sum is σ = 211431248. Its totient is φ = 211431246.

The previous prime is 211431197. The next prime is 211431313. The reversal of 211431247 is 742134112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211431247 - 2⁷ = 211431119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211431047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105715623 + 105715624.

It is an arithmetic number, because the mean of its divisors is an integer number (105715624).

Almost surely, 2^211431247 is an apocalyptic number.

211431247 is a deficient number, since it is larger than the sum of its proper divisors (1).

211431247 is an equidigital number, since it uses as much as digits as its factorization.

211431247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1344, while the sum is 25.

The square root of 211431247 is about 14540.6756032861. The cubic root of 211431247 is about 595.7394915354.

Adding to 211431247 its reverse (742134112), we get a palindrome (953565359).

The spelling of 211431247 in words is "two hundred eleven million, four hundred thirty-one thousand, two hundred forty-seven".