51665211 has 24 divisors (see below), whose sum is σ = 83144880. Its totient is φ = 30695616.

The previous prime is 51665203. The next prime is 51665219. The reversal of 51665211 is 11256615.

It is a happy number.

51665211 is a `hidden beast` number, since 5 + 1 + 6 + 652 + 1 + 1 = 666.

51665211 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51665203) and next prime (51665219).

It is not a de Polignac number, because 51665211 - 2³ = 51665203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51665219) 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 23 ways as a sum of consecutive naturals, for example, 4221 + ... + 11006.

It is an arithmetic number, because the mean of its divisors is an integer number (3464370).

Almost surely, 2^51665211 is an apocalyptic number.

51665211 is a deficient number, since it is larger than the sum of its proper divisors (31479669).

51665211 is a wasteful number, since it uses less digits than its factorization.

51665211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15275 (or 15272 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

The square root of 51665211 is about 7187.8516261815. The cubic root of 51665211 is about 372.4483624351.

The spelling of 51665211 in words is "fifty-one million, six hundred sixty-five thousand, two hundred eleven".