646947 has 30 divisors (see below), whose sum is σ = 1131108. Its totient is φ = 367416.

The previous prime is 646937. The next prime is 646957. The reversal of 646947 is 749646.

646947 is a `hidden beast` number, since 646 + 9 + 4 + 7 = 666.

It is an interprime number because it is at equal distance from previous prime (646937) and next prime (646957).

It is not a de Polignac number, because 646947 - 2⁶ = 646883 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

Its product of digits (36288) is a multiple of the sum of its prime factors (189).

It is a nialpdrome in base 7.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646947.

It is not an unprimeable number, because it can be changed into a prime (646927) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3888 + ... + 4050.

2⁶⁴⁶⁹⁴⁷ is an apocalyptic number.

646947 is a deficient number, since it is larger than the sum of its proper divisors (484161).

646947 is a wasteful number, since it uses less digits than its factorization.

646947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 173 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 646947 is about 804.3301560926. The cubic root of 646947 is about 86.4880756949.

The spelling of 646947 in words is "six hundred forty-six thousand, nine hundred forty-seven".