51587917 has 4 divisors (see below), whose sum is σ = 52787680. Its totient is φ = 50388156.

The previous prime is 51587909. The next prime is 51587951. The reversal of 51587917 is 71978515.

51587917 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 51587917 - 2³ = 51587909 is a prime.

It is a super-2 number, since 2×51587917² = 5322626360797778, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 1199719 = 51587917 / (5 + 1 + 5 + 8 + 7 + 9 + 1 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51587957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 599817 + ... + 599902.

It is an arithmetic number, because the mean of its divisors is an integer number (13196920).

Almost surely, 2^51587917 is an apocalyptic number.

It is an amenable number.

51587917 is a deficient number, since it is larger than the sum of its proper divisors (1199763).

51587917 is a wasteful number, since it uses less digits than its factorization.

51587917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1199762.

The product of its digits is 88200, while the sum is 43.

The square root of 51587917 is about 7182.4729028379. The cubic root of 51587917 is about 372.2625353168.

The spelling of 51587917 in words is "fifty-one million, five hundred eighty-seven thousand, nine hundred seventeen".