51791609 has 2 divisors, whose sum is σ = 51791610. Its totient is φ = 51791608.

The previous prime is 51791599. The next prime is 51791611. The reversal of 51791609 is 90619715.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51437584 + 354025 = 7172^2 + 595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51791609 is a prime.

Together with 51791611, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51791309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25895804 + 25895805.

It is an arithmetic number, because the mean of its divisors is an integer number (25895805).

Almost surely, 2^51791609 is an apocalyptic number.

It is an amenable number.

51791609 is a deficient number, since it is larger than the sum of its proper divisors (1).

51791609 is an equidigital number, since it uses as much as digits as its factorization.

51791609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17010, while the sum is 38.

The square root of 51791609 is about 7196.6387292958. The cubic root of 51791609 is about 372.7518444656.

The spelling of 51791609 in words is "fifty-one million, seven hundred ninety-one thousand, six hundred nine".