1215881171 has 2 divisors, whose sum is σ = 1215881172. Its totient is φ = 1215881170.

The previous prime is 1215881141. The next prime is 1215881189. The reversal of 1215881171 is 1711885121.

It is a strong prime.

It is an emirp because it is prime and its reverse (1711885121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1215881171 - 2¹⁴ = 1215864787 is a prime.

It is not a weakly prime, because it can be changed into another prime (1215881141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607940585 + 607940586.

It is an arithmetic number, because the mean of its divisors is an integer number (607940586).

Almost surely, 2^1215881171 is an apocalyptic number.

1215881171 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215881171 is an equidigital number, since it uses as much as digits as its factorization.

1215881171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4480, while the sum is 35.

The square root of 1215881171 is about 34869.4876790583. The cubic root of 1215881171 is about 1067.3258904286.

The spelling of 1215881171 in words is "one billion, two hundred fifteen million, eight hundred eighty-one thousand, one hundred seventy-one".