1725661 has 4 divisors (see below), whose sum is σ = 1972192. Its totient is φ = 1479132.

The previous prime is 1725641. The next prime is 1725671. The reversal of 1725661 is 1665271.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1725661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1725641) 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, 123255 + ... + 123268.

It is an arithmetic number, because the mean of its divisors is an integer number (493048).

2^1725661 is an apocalyptic number.

It is an amenable number.

1725661 is a deficient number, since it is larger than the sum of its proper divisors (246531).

1725661 is an equidigital number, since it uses as much as digits as its factorization.

1725661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246530.

The product of its digits is 2520, while the sum is 28.

The square root of 1725661 is about 1313.6441679542. The cubic root of 1725661 is about 119.9458320338.

The spelling of 1725661 in words is "one million, seven hundred twenty-five thousand, six hundred sixty-one".