5136878221 has 4 divisors (see below), whose sum is σ = 5156866332. Its totient is φ = 5116890112.

The previous prime is 5136878191. The next prime is 5136878249. The reversal of 5136878221 is 1228786315.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2585214025 + 2551664196 = 50845^2 + 50514^2 .

It is a cyclic number.

It is not a de Polignac number, because 5136878221 - 2⁵ = 5136878189 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 (5136878251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9993670 + ... + 9994183.

It is an arithmetic number, because the mean of its divisors is an integer number (1289216583).

Almost surely, 2^5136878221 is an apocalyptic number.

It is an amenable number.

5136878221 is a deficient number, since it is larger than the sum of its proper divisors (19988111).

5136878221 is a wasteful number, since it uses less digits than its factorization.

5136878221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19988110.

The product of its digits is 161280, while the sum is 43.

The square root of 5136878221 is about 71672.0183963030. The cubic root of 5136878221 is about 1725.4395822655.

The spelling of 5136878221 in words is "five billion, one hundred thirty-six million, eight hundred seventy-eight thousand, two hundred twenty-one".