1666425 has 24 divisors (see below), whose sum is σ = 2919456. Its totient is φ = 835840.

The previous prime is 1666421. The next prime is 1666429. The reversal of 1666425 is 5246661.

It is an interprime number because it is at equal distance from previous prime (1666421) and next prime (1666429).

It is not a de Polignac number, because 1666425 - 2² = 1666421 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1666392 and 1666401.

It is not an unprimeable number, because it can be changed into a prime (1666421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 622 + ... + 1928.

It is an arithmetic number, because the mean of its divisors is an integer number (121644).

2^1666425 is an apocalyptic number.

1666425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1666425 is a deficient number, since it is larger than the sum of its proper divisors (1253031).

1666425 is a wasteful number, since it uses less digits than its factorization.

1666425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1337 (or 1332 counting only the distinct ones).

The product of its digits is 8640, while the sum is 30.

The square root of 1666425 is about 1290.9008482451. The cubic root of 1666425 is about 118.5573793223.

The spelling of 1666425 in words is "one million, six hundred sixty-six thousand, four hundred twenty-five".