18891958843 has 2 divisors, whose sum is σ = 18891958844. Its totient is φ = 18891958842.

The previous prime is 18891958829. The next prime is 18891958907. The reversal of 18891958843 is 34885919881.

It is an a-pointer prime, because the next prime (18891958907) can be obtained adding 18891958843 to its sum of digits (64).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18891958843 - 2²⁹ = 18355087931 is a prime.

It is a super-2 number, since 2×18891958843² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18891959843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9445979421 + 9445979422.

It is an arithmetic number, because the mean of its divisors is an integer number (9445979422).

Almost surely, 2^18891958843 is an apocalyptic number.

18891958843 is a deficient number, since it is larger than the sum of its proper divisors (1).

18891958843 is an equidigital number, since it uses as much as digits as its factorization.

18891958843 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19906560, while the sum is 64.

The spelling of 18891958843 in words is "eighteen billion, eight hundred ninety-one million, nine hundred fifty-eight thousand, eight hundred forty-three".