51916985 has 4 divisors (see below), whose sum is σ = 62300388. Its totient is φ = 41533584.

The previous prime is 51916973. The next prime is 51917009. The reversal of 51916985 is 58961915.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6165289 + 45751696 = 2483^2 + 6764^2 .

It is a cyclic number.

It is not a de Polignac number, because 51916985 - 2¹⁴ = 51900601 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 5191694 + ... + 5191703.

It is an arithmetic number, because the mean of its divisors is an integer number (15575097).

Almost surely, 2^51916985 is an apocalyptic number.

It is an amenable number.

51916985 is a deficient number, since it is larger than the sum of its proper divisors (10383403).

51916985 is a wasteful number, since it uses less digits than its factorization.

51916985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10383402.

The product of its digits is 97200, while the sum is 44.

The square root of 51916985 is about 7205.3441971914. The cubic root of 51916985 is about 373.0523852661.

The spelling of 51916985 in words is "fifty-one million, nine hundred sixteen thousand, nine hundred eighty-five".