1663725 has 24 divisors (see below), whose sum is σ = 3144640. Its totient is φ = 760320.

The previous prime is 1663721. The next prime is 1663747. The reversal of 1663725 is 5273661.

It is not a de Polignac number, because 1663725 - 2² = 1663721 is a prime.

1663725 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1663692 and 1663701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1060 + ... + 2109.

2^1663725 is an apocalyptic number.

1663725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1663725 is a deficient number, since it is larger than the sum of its proper divisors (1480915).

1663725 is a wasteful number, since it uses less digits than its factorization.

1663725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3189 (or 3184 counting only the distinct ones).

The product of its digits is 7560, while the sum is 30.

The square root of 1663725 is about 1289.8546429734. The cubic root of 1663725 is about 118.4933144406.

The spelling of 1663725 in words is "one million, six hundred sixty-three thousand, seven hundred twenty-five".