646625 has 16 divisors (see below), whose sum is σ = 923520. Its totient is φ = 442800.

The previous prime is 646619. The next prime is 646631. The reversal of 646625 is 526646.

It is an interprime number because it is at equal distance from previous prime (646619) and next prime (646631).

It is a sliding number, since 646625 = 256000 + 390625 and 1/256000 + 1/390625 = 0.00000646625.

It is not a de Polignac number, because 646625 - 2⁴ = 646609 is a prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646625.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 506 + ... + 1244.

It is an arithmetic number, because the mean of its divisors is an integer number (57720).

2⁶⁴⁶⁶²⁵ is an apocalyptic number.

It is an amenable number.

646625 is a deficient number, since it is larger than the sum of its proper divisors (276895).

646625 is an equidigital number, since it uses as much as digits as its factorization.

646625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761 (or 751 counting only the distinct ones).

The product of its digits is 8640, while the sum is 29.

The square root of 646625 is about 804.1299646201. The cubic root of 646625 is about 86.4737242967.

The spelling of 646625 in words is "six hundred forty-six thousand, six hundred twenty-five".