18247661 has 2 divisors, whose sum is σ = 18247662. Its totient is φ = 18247660.

The previous prime is 18247643. The next prime is 18247679. The reversal of 18247661 is 16674281.

It is a balanced prime because it is at equal distance from previous prime (18247643) and next prime (18247679).

It can be written as a sum of positive squares in only one way, i.e., 17598025 + 649636 = 4195^2 + 806^2 .

It is a cyclic number.

It is not a de Polignac number, because 18247661 - 2²² = 14053357 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18277661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9123830 + 9123831.

It is an arithmetic number, because the mean of its divisors is an integer number (9123831).

Almost surely, 2^18247661 is an apocalyptic number.

It is an amenable number.

18247661 is a deficient number, since it is larger than the sum of its proper divisors (1).

18247661 is an equidigital number, since it uses as much as digits as its factorization.

18247661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 35.

The square root of 18247661 is about 4271.7281046434. The cubic root of 18247661 is about 263.2706231418.

The spelling of 18247661 in words is "eighteen million, two hundred forty-seven thousand, six hundred sixty-one".