1721085 has 16 divisors (see below), whose sum is σ = 2773440. Its totient is φ = 911360.

The previous prime is 1721081. The next prime is 1721123. The reversal of 1721085 is 5801271.

It is not a de Polignac number, because 1721085 - 2² = 1721081 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1721081) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2365 + ... + 3005.

It is an arithmetic number, because the mean of its divisors is an integer number (173340).

2^1721085 is an apocalyptic number.

1721085 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1721085 is a deficient number, since it is larger than the sum of its proper divisors (1052355).

1721085 is a wasteful number, since it uses less digits than its factorization.

1721085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828.

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 1721085 is about 1311.9012920186. The cubic root of 1721085 is about 119.8397165610.

The spelling of 1721085 in words is "one million, seven hundred twenty-one thousand, eighty-five".