1720965 has 16 divisors (see below), whose sum is σ = 2843136. Its totient is φ = 888000.

The previous prime is 1720951. The next prime is 1720973. The reversal of 1720965 is 5690271.

It is not a de Polignac number, because 1720965 - 2⁴ = 1720949 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1386 + ... + 2315.

It is an arithmetic number, because the mean of its divisors is an integer number (177696).

2^1720965 is an apocalyptic number.

1720965 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1720965 is a deficient number, since it is larger than the sum of its proper divisors (1122171).

1720965 is a wasteful number, since it uses less digits than its factorization.

1720965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3740.

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 1720965 is about 1311.8555560732. The cubic root of 1720965 is about 119.8369312831.

The spelling of 1720965 in words is "one million, seven hundred twenty thousand, nine hundred sixty-five".