5127917981 has 4 divisors (see below), whose sum is σ = 5147416032. Its totient is φ = 5108419932.

The previous prime is 5127917959. The next prime is 5127918007. The reversal of 5127917981 is 1897197215.

It is a happy number.

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 5127917981 - 2²² = 5123723677 is a prime.

It is a super-2 number, since 2×5127917981² = 52591085639726232722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5127917911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9748631 + ... + 9749156.

It is an arithmetic number, because the mean of its divisors is an integer number (1286854008).

Almost surely, 2^5127917981 is an apocalyptic number.

It is an amenable number.

5127917981 is a deficient number, since it is larger than the sum of its proper divisors (19498051).

5127917981 is a wasteful number, since it uses less digits than its factorization.

5127917981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19498050.

The product of its digits is 317520, while the sum is 50.

The square root of 5127917981 is about 71609.4824796270. The cubic root of 5127917981 is about 1724.4357721714.

The spelling of 5127917981 in words is "five billion, one hundred twenty-seven million, nine hundred seventeen thousand, nine hundred eighty-one".