1211516071 has 4 divisors (see below), whose sum is σ = 1220359392. Its totient is φ = 1202672752.

The previous prime is 1211516051. The next prime is 1211516081. The reversal of 1211516071 is 1706151121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1706151121 = 233 ⋅7322537.

It is a cyclic number.

It is not a de Polignac number, because 1211516071 - 2¹⁵ = 1211483303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211516041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4421455 + ... + 4421728.

It is an arithmetic number, because the mean of its divisors is an integer number (305089848).

Almost surely, 2^1211516071 is an apocalyptic number.

1211516071 is a deficient number, since it is larger than the sum of its proper divisors (8843321).

1211516071 is an equidigital number, since it uses as much as digits as its factorization.

1211516071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8843320.

The product of its (nonzero) digits is 420, while the sum is 25.

The square root of 1211516071 is about 34806.8394284801. The cubic root of 1211516071 is about 1066.0471002354.

Adding to 1211516071 its reverse (1706151121), we get a palindrome (2917667192).

The spelling of 1211516071 in words is "one billion, two hundred eleven million, five hundred sixteen thousand, seventy-one".