51539465 has 4 divisors (see below), whose sum is σ = 61847364. Its totient is φ = 41231568.

The previous prime is 51539443. The next prime is 51539491. The reversal of 51539465 is 56493515.

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 24364096 + 27175369 = 4936^2 + 5213^2 .

It is a cyclic number.

It is not a de Polignac number, because 51539465 - 2¹² = 51535369 is a prime.

It is a Duffinian number.

It is a Curzon 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, 5153942 + ... + 5153951.

It is an arithmetic number, because the mean of its divisors is an integer number (15461841).

Almost surely, 2^51539465 is an apocalyptic number.

It is an amenable number.

51539465 is a deficient number, since it is larger than the sum of its proper divisors (10307899).

51539465 is a wasteful number, since it uses less digits than its factorization.

51539465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10307898.

The product of its digits is 81000, while the sum is 38.

The square root of 51539465 is about 7179.0991774735. The cubic root of 51539465 is about 372.1459543086.

The spelling of 51539465 in words is "fifty-one million, five hundred thirty-nine thousand, four hundred sixty-five".