1720018 has 4 divisors (see below), whose sum is σ = 2580030. Its totient is φ = 860008.

The previous prime is 1720003. The next prime is 1720031. The reversal of 1720018 is 8100271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8100271 = 487 ⋅16633.

It can be written as a sum of positive squares in only one way, i.e., 1456849 + 263169 = 1207^2 + 513^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1719977 and 1720004.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430003 + ... + 430006.

2^1720018 is an apocalyptic number.

1720018 is a deficient number, since it is larger than the sum of its proper divisors (860012).

1720018 is an equidigital number, since it uses as much as digits as its factorization.

1720018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860011.

The product of its (nonzero) digits is 112, while the sum is 19.

The square root of 1720018 is about 1311.4945672781. The cubic root of 1720018 is about 119.8149462541.

Adding to 1720018 its reverse (8100271), we get a palindrome (9820289).

The spelling of 1720018 in words is "one million, seven hundred twenty thousand, eighteen".