646071625 has 8 divisors (see below), whose sum is σ = 806297544. Its totient is φ = 516857200.

The previous prime is 646071581. The next prime is 646071631. The reversal of 646071625 is 526170646.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 17867529 + 628204096 = 4227^2 + 25064^2 .

It is not a de Polignac number, because 646071625 - 2¹⁷ = 645940553 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2584162 + ... + 2584411.

It is an arithmetic number, because the mean of its divisors is an integer number (100787193).

Almost surely, 2^646071625 is an apocalyptic number.

It is an amenable number.

646071625 is a deficient number, since it is larger than the sum of its proper divisors (160225919).

646071625 is an equidigital number, since it uses as much as digits as its factorization.

646071625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5168588 (or 5168578 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 646071625 is about 25417.9390391904. The cubic root of 646071625 is about 864.4904948297.

The spelling of 646071625 in words is "six hundred forty-six million, seventy-one thousand, six hundred twenty-five".