1211665041 has 16 divisors (see below), whose sum is σ = 1799596800. Its totient is φ = 805734864.

The previous prime is 1211665033. The next prime is 1211665057. The reversal of 1211665041 is 1405661121.

1211665041 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 6 + 650 + 4 + 1 = 666.

It is not a de Polignac number, because 1211665041 - 2³ = 1211665033 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1211664996 and 1211665014.

It is not an unprimeable number, because it can be changed into a prime (1211665061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45801 + ... + 67238.

It is an arithmetic number, because the mean of its divisors is an integer number (112474800).

Almost surely, 2^1211665041 is an apocalyptic number.

It is an amenable number.

1211665041 is a deficient number, since it is larger than the sum of its proper divisors (587931759).

1211665041 is a wasteful number, since it uses less digits than its factorization.

1211665041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113445 (or 113439 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1211665041 is about 34808.9793156881. The cubic root of 1211665041 is about 1066.0907927437.

Adding to 1211665041 its product of nonzero digits (1440), we get a square (1211666481 = 34809²).

The spelling of 1211665041 in words is "one billion, two hundred eleven million, six hundred sixty-five thousand, forty-one".