18616061 has 2 divisors, whose sum is σ = 18616062. Its totient is φ = 18616060.

The previous prime is 18616007. The next prime is 18616063. The reversal of 18616061 is 16061681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18232900 + 383161 = 4270^2 + 619^2 .

It is an emirp because it is prime and its reverse (16061681) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 19091981 and 18919091.

It is a cyclic number.

It is not a de Polignac number, because 18616061 - 2⁶ = 18615997 is a prime.

Together with 18616063, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18616063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9308030 + 9308031.

It is an arithmetic number, because the mean of its divisors is an integer number (9308031).

Almost surely, 2^18616061 is an apocalyptic number.

It is an amenable number.

18616061 is a deficient number, since it is larger than the sum of its proper divisors (1).

18616061 is an equidigital number, since it uses as much as digits as its factorization.

18616061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 18616061 is about 4314.6333563815. The cubic root of 18616061 is about 265.0305459034.

The spelling of 18616061 in words is "eighteen million, six hundred sixteen thousand, sixty-one".