1211162081 has 2 divisors, whose sum is σ = 1211162082. Its totient is φ = 1211162080.

The previous prime is 1211162039. The next prime is 1211162179. The reversal of 1211162081 is 1802611121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 664350625 + 546811456 = 25775^2 + 23384^2 .

It is an emirp because it is prime and its reverse (1802611121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211162081 - 2¹⁰ = 1211161057 is a prime.

It is a super-2 number, since 2×1211162081² = 2933827172904501122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1211162021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605581040 + 605581041.

It is an arithmetic number, because the mean of its divisors is an integer number (605581041).

Almost surely, 2^1211162081 is an apocalyptic number.

It is an amenable number.

1211162081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211162081 is an equidigital number, since it uses as much as digits as its factorization.

1211162081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 23.

The square root of 1211162081 is about 34801.7539931539. The cubic root of 1211162081 is about 1065.9432615322.

The spelling of 1211162081 in words is "one billion, two hundred eleven million, one hundred sixty-two thousand, eighty-one".