71611121 has 16 divisors (see below), whose sum is σ = 78140160. Its totient is φ = 65419200.

The previous prime is 71611117. The next prime is 71611139. The reversal of 71611121 is 12111617.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 71611121 - 2² = 71611117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 71611093 and 71611102.

It is not an unprimeable number, because it can be changed into a prime (71611721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66836 + ... + 67898.

It is an arithmetic number, because the mean of its divisors is an integer number (4883760).

Almost surely, 2^71611121 is an apocalyptic number.

It is an amenable number.

71611121 is a deficient number, since it is larger than the sum of its proper divisors (6529039).

71611121 is a wasteful number, since it uses less digits than its factorization.

71611121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1216.

The product of its digits is 84, while the sum is 20.

The square root of 71611121 is about 8462.3354341458. The cubic root of 71611121 is about 415.2664297769.

Adding to 71611121 its reverse (12111617), we get a palindrome (83722738).

The spelling of 71611121 in words is "seventy-one million, six hundred eleven thousand, one hundred twenty-one".