646270657 has 8 divisors (see below), whose sum is σ = 684585000. Its totient is φ = 607989504.

The previous prime is 646270649. The next prime is 646270673. The reversal of 646270657 is 756072646.

It can be written as a sum of positive squares in 4 ways, for example, as 11029041 + 635241616 = 3321^2 + 25204^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 646270657 - 2³ = 646270649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646270687) 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 7 ways as a sum of consecutive naturals, for example, 39819 + ... + 53647.

It is an arithmetic number, because the mean of its divisors is an integer number (85573125).

Almost surely, 2^646270657 is an apocalyptic number.

It is an amenable number.

646270657 is a deficient number, since it is larger than the sum of its proper divisors (38314343).

646270657 is a wasteful number, since it uses less digits than its factorization.

646270657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16595.

The product of its (nonzero) digits is 423360, while the sum is 43.

The square root of 646270657 is about 25421.8539253139. The cubic root of 646270657 is about 864.5792587788.

The spelling of 646270657 in words is "six hundred forty-six million, two hundred seventy thousand, six hundred fifty-seven".