8121318473 has 2 divisors, whose sum is σ = 8121318474. Its totient is φ = 8121318472.

The previous prime is 8121318467. The next prime is 8121318493. The reversal of 8121318473 is 3748131218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6569588809 + 1551729664 = 81053^2 + 39392^2 .

It is a cyclic number.

It is not a de Polignac number, because 8121318473 - 2¹⁴ = 8121302089 is a prime.

It is not a weakly prime, because it can be changed into another prime (8121318493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4060659236 + 4060659237.

It is an arithmetic number, because the mean of its divisors is an integer number (4060659237).

Almost surely, 2^8121318473 is an apocalyptic number.

It is an amenable number.

8121318473 is a deficient number, since it is larger than the sum of its proper divisors (1).

8121318473 is an equidigital number, since it uses as much as digits as its factorization.

8121318473 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 38.

The square root of 8121318473 is about 90118.3581352878. The cubic root of 8121318473 is about 2010.0591942337.

The spelling of 8121318473 in words is "eight billion, one hundred twenty-one million, three hundred eighteen thousand, four hundred seventy-three".