18857273861 has 2 divisors, whose sum is σ = 18857273862. Its totient is φ = 18857273860.

The previous prime is 18857273803. The next prime is 18857273863. The reversal of 18857273861 is 16837275881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17981469025 + 875804836 = 134095^2 + 29594^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18857273861 is a prime.

Together with 18857273863, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18857273797 and 18857273806.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18857273863) 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, 9428636930 + 9428636931.

It is an arithmetic number, because the mean of its divisors is an integer number (9428636931).

Almost surely, 2^18857273861 is an apocalyptic number.

It is an amenable number.

18857273861 is a deficient number, since it is larger than the sum of its proper divisors (1).

18857273861 is an equidigital number, since it uses as much as digits as its factorization.

18857273861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4515840, while the sum is 56.

The spelling of 18857273861 in words is "eighteen billion, eight hundred fifty-seven million, two hundred seventy-three thousand, eight hundred sixty-one".