646973225 has 12 divisors (see below), whose sum is σ = 804787404. Its totient is φ = 515939520.

The previous prime is 646973213. The next prime is 646973269. The reversal of 646973225 is 522379646.

It can be written as a sum of positive squares in 6 ways, for example, as 60171049 + 586802176 = 7757^2 + 24224^2 .

It is not a de Polignac number, because 646973225 - 2¹⁴ = 646956841 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 11 ways as a sum of consecutive naturals, for example, 32894 + ... + 48743.

It is an arithmetic number, because the mean of its divisors is an integer number (67065617).

Almost surely, 2^646973225 is an apocalyptic number.

It is an amenable number.

646973225 is a deficient number, since it is larger than the sum of its proper divisors (157814179).

646973225 is a wasteful number, since it uses less digits than its factorization.

646973225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81964 (or 81959 counting only the distinct ones).

The product of its digits is 544320, while the sum is 44.

The square root of 646973225 is about 25435.6683615745. The cubic root of 646973225 is about 864.8924432183.

The spelling of 646973225 in words is "six hundred forty-six million, nine hundred seventy-three thousand, two hundred twenty-five".