1723649 has 4 divisors (see below), whose sum is σ = 1726980. Its totient is φ = 1720320.

The previous prime is 1723639. The next prime is 1723651. The reversal of 1723649 is 9463271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 753424 + 970225 = 868^2 + 985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1723649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1723609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 704 + ... + 1985.

It is an arithmetic number, because the mean of its divisors is an integer number (431745).

2^1723649 is an apocalyptic number.

It is an amenable number.

1723649 is a deficient number, since it is larger than the sum of its proper divisors (3331).

1723649 is an equidigital number, since it uses as much as digits as its factorization.

1723649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3330.

The product of its digits is 9072, while the sum is 32.

The square root of 1723649 is about 1312.8781360050. The cubic root of 1723649 is about 119.8991977553.

The spelling of 1723649 in words is "one million, seven hundred twenty-three thousand, six hundred forty-nine".