1664025 has 24 divisors (see below), whose sum is σ = 3002784. Its totient is φ = 806400.

The previous prime is 1664021. The next prime is 1664053. The reversal of 1664025 is 5204661.

It is not a de Polignac number, because 1664025 - 2² = 1664021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1663986 and 1664004.

It is not an unprimeable number, because it can be changed into a prime (1664021) 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, 184 + ... + 1833.

It is an arithmetic number, because the mean of its divisors is an integer number (125116).

2^1664025 is an apocalyptic number.

1664025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1664025 is a deficient number, since it is larger than the sum of its proper divisors (1338759).

1664025 is a wasteful number, since it uses less digits than its factorization.

1664025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2041 (or 2036 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 1664025 is about 1289.9709299050. The cubic root of 1664025 is about 118.5004361821.

Adding to 1664025 its reverse (5204661), we get a palindrome (6868686).

The spelling of 1664025 in words is "one million, six hundred sixty-four thousand, twenty-five".