18649121 has 2 divisors, whose sum is σ = 18649122. Its totient is φ = 18649120.

The previous prime is 18649109. The next prime is 18649129. The reversal of 18649121 is 12194681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15880225 + 2768896 = 3985^2 + 1664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18649121 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18649129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9324560 + 9324561.

It is an arithmetic number, because the mean of its divisors is an integer number (9324561).

Almost surely, 2^18649121 is an apocalyptic number.

It is an amenable number.

18649121 is a deficient number, since it is larger than the sum of its proper divisors (1).

18649121 is an equidigital number, since it uses as much as digits as its factorization.

18649121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 32.

The square root of 18649121 is about 4318.4628052121. The cubic root of 18649121 is about 265.1873411252.

The spelling of 18649121 in words is "eighteen million, six hundred forty-nine thousand, one hundred twenty-one".