646425760 has 24 divisors (see below), whose sum is σ = 1527181236. Its totient is φ = 258570240.

The previous prime is 646425737. The next prime is 646425761. The reversal of 646425760 is 67524646.

It can be written as a sum of positive squares in 2 ways, for example, as 644956816 + 1468944 = 25396^2 + 1212^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (646425761) 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 3 ways as a sum of consecutive naturals, for example, 2019921 + ... + 2020240.

Almost surely, 2^646425760 is an apocalyptic number.

It is an amenable number.

646425760 is an abundant number, since it is smaller than the sum of its proper divisors (880755476).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646425760 is a wasteful number, since it uses less digits than its factorization.

646425760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4040176 (or 4040168 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 646425760 is about 25424.9043262703. The cubic root of 646425760 is about 864.6484187141.

The spelling of 646425760 in words is "six hundred forty-six million, four hundred twenty-five thousand, seven hundred sixty".