71112121 has 2 divisors, whose sum is σ = 71112122. Its totient is φ = 71112120.

The previous prime is 71112103. The next prime is 71112131. The reversal of 71112121 is 12121117.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69956496 + 1155625 = 8364^2 + 1075^2 .

It is a cyclic number.

It is not a de Polignac number, because 71112121 - 2¹¹ = 71110073 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 71112095 and 71112104.

It is not a weakly prime, because it can be changed into another prime (71112101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35556060 + 35556061.

It is an arithmetic number, because the mean of its divisors is an integer number (35556061).

Almost surely, 2^71112121 is an apocalyptic number.

It is an amenable number.

71112121 is a deficient number, since it is larger than the sum of its proper divisors (1).

71112121 is an equidigital number, since it uses as much as digits as its factorization.

71112121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28, while the sum is 16.

The square root of 71112121 is about 8432.8003059482. The cubic root of 71112121 is about 414.2996286760.

Adding to 71112121 its reverse (12121117), we get a palindrome (83233238).

The spelling of 71112121 in words is "seventy-one million, one hundred twelve thousand, one hundred twenty-one".