1720939 has 8 divisors (see below), whose sum is σ = 1897200. Its totient is φ = 1548000.

The previous prime is 1720937. The next prime is 1720949. The reversal of 1720939 is 9390271.

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 1720939 - 2¹ = 1720937 is a prime.

It is a Duffinian number.

1720939 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1720939.

It is not an unprimeable number, because it can be changed into a prime (1720931) 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, 337 + ... + 1885.

It is an arithmetic number, because the mean of its divisors is an integer number (237150).

2^1720939 is an apocalyptic number.

1720939 is a deficient number, since it is larger than the sum of its proper divisors (176261).

1720939 is a wasteful number, since it uses less digits than its factorization.

1720939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661.

The product of its (nonzero) digits is 3402, while the sum is 31.

The square root of 1720939 is about 1311.8456464081. The cubic root of 1720939 is about 119.8363277891.

The spelling of 1720939 in words is "one million, seven hundred twenty thousand, nine hundred thirty-nine".