18660437 has 2 divisors, whose sum is σ = 18660438. Its totient is φ = 18660436.

The previous prime is 18660401. The next prime is 18660463. The reversal of 18660437 is 73406681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17648401 + 1012036 = 4201^2 + 1006^2 .

It is an emirp because it is prime and its reverse (73406681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18660437 - 2¹⁰ = 18659413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18660397 and 18660406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18660487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9330218 + 9330219.

It is an arithmetic number, because the mean of its divisors is an integer number (9330219).

Almost surely, 2^18660437 is an apocalyptic number.

It is an amenable number.

18660437 is a deficient number, since it is larger than the sum of its proper divisors (1).

18660437 is an equidigital number, since it uses as much as digits as its factorization.

18660437 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 18660437 is about 4319.7727949511. The cubic root of 18660437 is about 265.2409674811.

The spelling of 18660437 in words is "eighteen million, six hundred sixty thousand, four hundred thirty-seven".