18641843431 has 2 divisors, whose sum is σ = 18641843432. Its totient is φ = 18641843430.

The previous prime is 18641843417. The next prime is 18641843443. The reversal of 18641843431 is 13434814681.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18641843431 - 2¹³ = 18641835239 is a prime.

It is a super-2 number, since 2×18641843431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18641843411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9320921715 + 9320921716.

It is an arithmetic number, because the mean of its divisors is an integer number (9320921716).

Almost surely, 2^18641843431 is an apocalyptic number.

18641843431 is a deficient number, since it is larger than the sum of its proper divisors (1).

18641843431 is an equidigital number, since it uses as much as digits as its factorization.

18641843431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 43.

The spelling of 18641843431 in words is "eighteen billion, six hundred forty-one million, eight hundred forty-three thousand, four hundred thirty-one".