18434439431 has 2 divisors, whose sum is σ = 18434439432. Its totient is φ = 18434439430.

The previous prime is 18434439427. The next prime is 18434439451. The reversal of 18434439431 is 13493443481.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18434439431 - 2² = 18434439427 is a prime.

It is a super-2 number, since 2×18434439431² (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 (18434439421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9217219715 + 9217219716.

It is an arithmetic number, because the mean of its divisors is an integer number (9217219716).

Almost surely, 2^18434439431 is an apocalyptic number.

18434439431 is a deficient number, since it is larger than the sum of its proper divisors (1).

18434439431 is an equidigital number, since it uses as much as digits as its factorization.

18434439431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 497664, while the sum is 44.

The spelling of 18434439431 in words is "eighteen billion, four hundred thirty-four million, four hundred thirty-nine thousand, four hundred thirty-one".