646663101 has 64 divisors (see below), whose sum is σ = 1058365440. Its totient is φ = 343284480.

The previous prime is 646663093. The next prime is 646663109. The reversal of 646663101 is 101366646.

It is an interprime number because it is at equal distance from previous prime (646663093) and next prime (646663109).

It is not a de Polignac number, because 646663101 - 2³ = 646663093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646663109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3737851 + ... + 3738023.

It is an arithmetic number, because the mean of its divisors is an integer number (16536960).

Almost surely, 2^646663101 is an apocalyptic number.

It is an amenable number.

646663101 is a deficient number, since it is larger than the sum of its proper divisors (411702339).

646663101 is a wasteful number, since it uses less digits than its factorization.

646663101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386.

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 646663101 is about 25429.5713884446. The cubic root of 646663101 is about 864.7542268994.

The spelling of 646663101 in words is "six hundred forty-six million, six hundred sixty-three thousand, one hundred one".