51171609 has 4 divisors (see below), whose sum is σ = 68228816. Its totient is φ = 34114404.

The previous prime is 51171583. The next prime is 51171691. The reversal of 51171609 is 90617115.

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 not a de Polignac number, because 51171609 - 2⁸ = 51171353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51171709) by changing a digit.

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, 8528599 + ... + 8528604.

It is an arithmetic number, because the mean of its divisors is an integer number (17057204).

Almost surely, 2^51171609 is an apocalyptic number.

It is an amenable number.

51171609 is a deficient number, since it is larger than the sum of its proper divisors (17057207).

51171609 is a wasteful number, since it uses less digits than its factorization.

51171609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17057206.

The product of its (nonzero) digits is 1890, while the sum is 30.

The square root of 51171609 is about 7153.4333714658. The cubic root of 51171609 is about 371.2584589214.

The spelling of 51171609 in words is "fifty-one million, one hundred seventy-one thousand, six hundred nine".