18648121 has 2 divisors, whose sum is σ = 18648122. Its totient is φ = 18648120.

The previous prime is 18648109. The next prime is 18648137. The reversal of 18648121 is 12184681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16088121 + 2560000 = 4011^2 + 1600^2 .

It is a cyclic number.

It is not a de Polignac number, because 18648121 - 2⁵ = 18648089 is a prime.

It is not a weakly prime, because it can be changed into another prime (18648151) 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, 9324060 + 9324061.

It is an arithmetic number, because the mean of its divisors is an integer number (9324061).

Almost surely, 2^18648121 is an apocalyptic number.

It is an amenable number.

18648121 is a deficient number, since it is larger than the sum of its proper divisors (1).

18648121 is an equidigital number, since it uses as much as digits as its factorization.

18648121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3072, while the sum is 31.

The square root of 18648121 is about 4318.3470217202. The cubic root of 18648121 is about 265.1826010969.

It can be divided in two parts, 18648 and 121, that added together give a square (18769 = 137²).

The spelling of 18648121 in words is "eighteen million, six hundred forty-eight thousand, one hundred twenty-one".