18676661 has 2 divisors, whose sum is σ = 18676662. Its totient is φ = 18676660.

The previous prime is 18676649. The next prime is 18676673. The reversal of 18676661 is 16667681.

It is a balanced prime because it is at equal distance from previous prime (18676649) and next prime (18676673).

It can be written as a sum of positive squares in only one way, i.e., 13359025 + 5317636 = 3655^2 + 2306^2 .

It is an emirp because it is prime and its reverse (16667681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18676661 - 2⁶ = 18676597 is a prime.

It is a super-2 number, since 2×18676661² = 697635332217842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18670661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9338330 + 9338331.

It is an arithmetic number, because the mean of its divisors is an integer number (9338331).

Almost surely, 2^18676661 is an apocalyptic number.

It is an amenable number.

18676661 is a deficient number, since it is larger than the sum of its proper divisors (1).

18676661 is an equidigital number, since it uses as much as digits as its factorization.

18676661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 41.

The square root of 18676661 is about 4321.6502634989. The cubic root of 18676661 is about 265.3178149655.

The spelling of 18676661 in words is "eighteen million, six hundred seventy-six thousand, six hundred sixty-one".