1660247 has 2 divisors, whose sum is σ = 1660248. Its totient is φ = 1660246.

The previous prime is 1660231. The next prime is 1660259. The reversal of 1660247 is 7420661.

It is a strong prime.

It is an emirp because it is prime and its reverse (7420661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1660247 - 2⁴ = 1660231 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1660207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830123 + 830124.

It is an arithmetic number, because the mean of its divisors is an integer number (830124).

2^1660247 is an apocalyptic number.

1660247 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660247 is an equidigital number, since it uses as much as digits as its factorization.

1660247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 1660247 is about 1288.5057236970. The cubic root of 1660247 is about 118.4106871516.

The spelling of 1660247 in words is "one million, six hundred sixty thousand, two hundred forty-seven".