1720663 has 8 divisors (see below), whose sum is σ = 1974560. Its totient is φ = 1468800.

The previous prime is 1720643. The next prime is 1720669. The reversal of 1720663 is 3660271.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1720663 - 2⁹ = 1720151 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2563 + ... + 3163.

It is an arithmetic number, because the mean of its divisors is an integer number (246820).

2^1720663 is an apocalyptic number.

1720663 is a deficient number, since it is larger than the sum of its proper divisors (253897).

1720663 is an equidigital number, since it uses as much as digits as its factorization.

1720663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1017.

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 1720663 is about 1311.7404468873. The cubic root of 1720663 is about 119.8299210940.

The spelling of 1720663 in words is "one million, seven hundred twenty thousand, six hundred sixty-three".