5191778917 has 8 divisors (see below), whose sum is σ = 5606990424. Its totient is φ = 4778830848.

The previous prime is 5191778897. The next prime is 5191778939. The reversal of 5191778917 is 7198771915.

It is a Cunningham number, because it is equal to 72054²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 768065796 + 4423713121 = 27714^2 + 66511^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 5191778917 - 2⁷ = 5191778789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5191778947) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 561088 + ... + 570265.

It is an arithmetic number, because the mean of its divisors is an integer number (700873803).

Almost surely, 2^5191778917 is an apocalyptic number.

It is an amenable number.

5191778917 is a deficient number, since it is larger than the sum of its proper divisors (415211507).

5191778917 is a wasteful number, since it uses less digits than its factorization.

5191778917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1131719.

The product of its digits is 1111320, while the sum is 55.

The square root of 5191778917 is about 72054.0000069392. Note that the first 5 decimals coincide. The cubic root of 5191778917 is about 1731.5647260896.

The spelling of 5191778917 in words is "five billion, one hundred ninety-one million, seven hundred seventy-eight thousand, nine hundred seventeen".