646223624 has 8 divisors (see below), whose sum is σ = 1211669310. Its totient is φ = 323111808.

The previous prime is 646223623. The next prime is 646223639. The reversal of 646223624 is 426322646.

It can be written as a sum of positive squares in only one way, i.e., 596238724 + 49984900 = 24418^2 + 7070^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (646223621) by changing a digit.

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 as a sum of consecutive naturals, namely, 40388969 + ... + 40388984.

Almost surely, 2^646223624 is an apocalyptic number.

It is an amenable number.

646223624 is a deficient number, since it is larger than the sum of its proper divisors (565445686).

646223624 is a wasteful number, since it uses less digits than its factorization.

646223624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80777959 (or 80777955 counting only the distinct ones).

The product of its digits is 82944, while the sum is 35.

The square root of 646223624 is about 25420.9288579312. The cubic root of 646223624 is about 864.5582847270.

The spelling of 646223624 in words is "six hundred forty-six million, two hundred twenty-three thousand, six hundred twenty-four".