641821252 has 6 divisors (see below), whose sum is σ = 1123187198. Its totient is φ = 320910624.

The previous prime is 641821231. The next prime is 641821253. The reversal of 641821252 is 252128146.

It can be written as a sum of positive squares in only one way, i.e., 462422016 + 179399236 = 21504^2 + 13394^2 .

It is not an unprimeable number, because it can be changed into a prime (641821253) 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, 80227653 + ... + 80227660.

Almost surely, 2^641821252 is an apocalyptic number.

It is an amenable number.

641821252 is a deficient number, since it is larger than the sum of its proper divisors (481365946).

641821252 is a wasteful number, since it uses less digits than its factorization.

641821252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160455317 (or 160455315 counting only the distinct ones).

The product of its digits is 7680, while the sum is 31.

The square root of 641821252 is about 25334.1913626624. The cubic root of 641821252 is about 862.5905535955.

Adding to 641821252 its reverse (252128146), we get a palindrome (893949398).

The spelling of 641821252 in words is "six hundred forty-one million, eight hundred twenty-one thousand, two hundred fifty-two".