1211666471 has 2 divisors, whose sum is σ = 1211666472. Its totient is φ = 1211666470.

The previous prime is 1211666441. The next prime is 1211666501. The reversal of 1211666471 is 1746661121.

It is a balanced prime because it is at equal distance from previous prime (1211666441) and next prime (1211666501).

It is a cyclic number.

It is not a de Polignac number, because 1211666471 - 2²⁶ = 1144557607 is a prime.

It is a super-3 number, since 3×1211666471³ (a number of 28 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211666441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605833235 + 605833236.

It is an arithmetic number, because the mean of its divisors is an integer number (605833236).

Almost surely, 2^1211666471 is an apocalyptic number.

1211666471 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211666471 is an equidigital number, since it uses as much as digits as its factorization.

1211666471 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 1211666471 is about 34808.9998563590. Note that the first 3 decimals coincide. The cubic root of 1211666471 is about 1066.0912121416.

It can be divided in two parts, 12116 and 66471, that added together give a palindrome (78587).

The spelling of 1211666471 in words is "one billion, two hundred eleven million, six hundred sixty-six thousand, four hundred seventy-one".