8138605931 has 2 divisors, whose sum is σ = 8138605932. Its totient is φ = 8138605930.

The previous prime is 8138605861. The next prime is 8138605933. The reversal of 8138605931 is 1395068318.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8138605931 is a prime.

It is a super-2 number, since 2×8138605931² (a number of 21 digits) contains 22 as substring.

Together with 8138605933, 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 (8138605933) 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 as a sum of consecutive naturals, namely, 4069302965 + 4069302966.

It is an arithmetic number, because the mean of its divisors is an integer number (4069302966).

Almost surely, 2^8138605931 is an apocalyptic number.

8138605931 is a deficient number, since it is larger than the sum of its proper divisors (1).

8138605931 is an equidigital number, since it uses as much as digits as its factorization.

8138605931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 44.

The square root of 8138605931 is about 90214.2224430272. Note that the first 3 decimals coincide. The cubic root of 8138605931 is about 2011.4844220499.

The spelling of 8138605931 in words is "eight billion, one hundred thirty-eight million, six hundred five thousand, nine hundred thirty-one".