51885765 has 20 divisors (see below), whose sum is σ = 93010764. Its totient is φ = 27672192.

The previous prime is 51885749. The next prime is 51885773. The reversal of 51885765 is 56758815.

It can be written as a sum of positive squares in 2 ways, for example, as 11512449 + 40373316 = 3393^2 + 6354^2 .

It is not a de Polignac number, because 51885765 - 2⁴ = 51885749 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 51885765.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 63652 + ... + 64461.

Almost surely, 2^51885765 is an apocalyptic number.

It is an amenable number.

51885765 is a deficient number, since it is larger than the sum of its proper divisors (41124999).

51885765 is a wasteful number, since it uses less digits than its factorization.

51885765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128130 (or 128121 counting only the distinct ones).

The product of its digits is 336000, while the sum is 45.

The square root of 51885765 is about 7203.1774238873. The cubic root of 51885765 is about 372.9775925895.

It can be divided in two parts, 51885 and 765, that added together give a triangular number (52650 = T₃₂₄).

The spelling of 51885765 in words is "fifty-one million, eight hundred eighty-five thousand, seven hundred sixty-five".