51585509 has 4 divisors (see below), whose sum is σ = 52785216. Its totient is φ = 50385804.

The previous prime is 51585487. The next prime is 51585539. The reversal of 51585509 is 90558515.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51585509 - 2¹⁶ = 51519973 is a prime.

It is a super-2 number, since 2×51585509² = 5322129477578162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51585539) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 599789 + ... + 599874.

It is an arithmetic number, because the mean of its divisors is an integer number (13196304).

Almost surely, 2^51585509 is an apocalyptic number.

It is an amenable number.

51585509 is a deficient number, since it is larger than the sum of its proper divisors (1199707).

51585509 is a wasteful number, since it uses less digits than its factorization.

51585509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1199706.

The product of its (nonzero) digits is 45000, while the sum is 38.

The square root of 51585509 is about 7182.3052705938. The cubic root of 51585509 is about 372.2567431198.

The spelling of 51585509 in words is "fifty-one million, five hundred eighty-five thousand, five hundred nine".