1725991 has 2 divisors, whose sum is σ = 1725992. Its totient is φ = 1725990.

The previous prime is 1725967. The next prime is 1726003. The reversal of 1725991 is 1995271.

It is a strong prime.

It is an emirp because it is prime and its reverse (1995271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1725991 - 2¹⁹ = 1201703 is a prime.

It is an Ulam number.

1725991 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1725931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 862995 + 862996.

It is an arithmetic number, because the mean of its divisors is an integer number (862996).

2^1725991 is an apocalyptic number.

1725991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1725991 is an equidigital number, since it uses as much as digits as its factorization.

1725991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5670, while the sum is 34.

The square root of 1725991 is about 1313.7697667400. The cubic root of 1725991 is about 119.9534773364.

The spelling of 1725991 in words is "one million, seven hundred twenty-five thousand, nine hundred ninety-one".