51605517 has 16 divisors (see below), whose sum is σ = 70357248. Its totient is φ = 33633600.

The previous prime is 51605503. The next prime is 51605527. The reversal of 51605517 is 71550615.

It is not a de Polignac number, because 51605517 - 2¹⁰ = 51604493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51605527) 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, 73267 + ... + 73967.

It is an arithmetic number, because the mean of its divisors is an integer number (4397328).

Almost surely, 2^51605517 is an apocalyptic number.

It is an amenable number.

51605517 is a deficient number, since it is larger than the sum of its proper divisors (18751731).

51605517 is a wasteful number, since it uses less digits than its factorization.

51605517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1220.

The product of its (nonzero) digits is 5250, while the sum is 30.

The square root of 51605517 is about 7183.6980031179. The cubic root of 51605517 is about 372.3048648393.

The spelling of 51605517 in words is "fifty-one million, six hundred five thousand, five hundred seventeen".