641002421 has 2 divisors, whose sum is σ = 641002422. Its totient is φ = 641002420.

The previous prime is 641002381. The next prime is 641002441. The reversal of 641002421 is 124200146.

It is an a-pointer prime, because the next prime (641002441) can be obtained adding 641002421 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 620707396 + 20295025 = 24914^2 + 4505^2 .

It is a cyclic number.

It is not a de Polignac number, because 641002421 - 2¹⁰ = 641001397 is a prime.

It is a super-2 number, since 2×641002421² = 821768207455722482, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 641002393 and 641002402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641002441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320501210 + 320501211.

It is an arithmetic number, because the mean of its divisors is an integer number (320501211).

Almost surely, 2^641002421 is an apocalyptic number.

It is an amenable number.

641002421 is a deficient number, since it is larger than the sum of its proper divisors (1).

641002421 is an equidigital number, since it uses as much as digits as its factorization.

641002421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 641002421 is about 25318.0256141746. The cubic root of 641002421 is about 862.2235685159.

Adding to 641002421 its reverse (124200146), we get a palindrome (765202567).

The spelling of 641002421 in words is "six hundred forty-one million, two thousand, four hundred twenty-one".