211691479 has 2 divisors, whose sum is σ = 211691480. Its totient is φ = 211691478.

The previous prime is 211691453. The next prime is 211691489. The reversal of 211691479 is 974196112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211691479 - 2¹⁹ = 211167191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211691419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105845739 + 105845740.

It is an arithmetic number, because the mean of its divisors is an integer number (105845740).

Almost surely, 2^211691479 is an apocalyptic number.

211691479 is a deficient number, since it is larger than the sum of its proper divisors (1).

211691479 is an equidigital number, since it uses as much as digits as its factorization.

211691479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 40.

The square root of 211691479 is about 14549.6212665485. The cubic root of 211691479 is about 595.9838056573.

The spelling of 211691479 in words is "two hundred eleven million, six hundred ninety-one thousand, four hundred seventy-nine".