18656129 has 2 divisors, whose sum is σ = 18656130. Its totient is φ = 18656128.

The previous prime is 18656117. The next prime is 18656137. The reversal of 18656129 is 92165681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14025025 + 4631104 = 3745^2 + 2152^2 .

It is a cyclic number.

It is not a de Polignac number, because 18656129 - 2⁸ = 18655873 is a prime.

It is a super-2 number, since 2×18656129² = 696102298529282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18656092 and 18656101.

It is not a weakly prime, because it can be changed into another prime (18656149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9328064 + 9328065.

It is an arithmetic number, because the mean of its divisors is an integer number (9328065).

Almost surely, 2^18656129 is an apocalyptic number.

It is an amenable number.

18656129 is a deficient number, since it is larger than the sum of its proper divisors (1).

18656129 is an equidigital number, since it uses as much as digits as its factorization.

18656129 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 38.

The square root of 18656129 is about 4319.2741288323. The cubic root of 18656129 is about 265.2205544895.

The spelling of 18656129 in words is "eighteen million, six hundred fifty-six thousand, one hundred twenty-nine".