18434439677 has 2 divisors, whose sum is σ = 18434439678. Its totient is φ = 18434439676.

The previous prime is 18434439631. The next prime is 18434439707. The reversal of 18434439677 is 77693443481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16607219161 + 1827220516 = 128869^2 + 42746^2 .

It is a cyclic number.

It is not a de Polignac number, because 18434439677 - 2⁸ = 18434439421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18434409677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9217219838 + 9217219839.

It is an arithmetic number, because the mean of its divisors is an integer number (9217219839).

Almost surely, 2^18434439677 is an apocalyptic number.

It is an amenable number.

18434439677 is a deficient number, since it is larger than the sum of its proper divisors (1).

18434439677 is an equidigital number, since it uses as much as digits as its factorization.

18434439677 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12192768, while the sum is 56.

The spelling of 18434439677 in words is "eighteen billion, four hundred thirty-four million, four hundred thirty-nine thousand, six hundred seventy-seven".