51165215 has 4 divisors (see below), whose sum is σ = 61398264. Its totient is φ = 40932168.

The previous prime is 51165203. The next prime is 51165217. The reversal of 51165215 is 51256115.

51165215 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51256115 = 5 ⋅10251223.

It is a cyclic number.

It is not a de Polignac number, because 51165215 - 2⁴ = 51165199 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 (51165217) 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, 5116517 + ... + 5116526.

It is an arithmetic number, because the mean of its divisors is an integer number (15349566).

Almost surely, 2^51165215 is an apocalyptic number.

51165215 is a deficient number, since it is larger than the sum of its proper divisors (10233049).

51165215 is a wasteful number, since it uses less digits than its factorization.

51165215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10233048.

The product of its digits is 1500, while the sum is 26.

The square root of 51165215 is about 7152.9864392434. The cubic root of 51165215 is about 371.2429951026.

The spelling of 51165215 in words is "fifty-one million, one hundred sixty-five thousand, two hundred fifteen".