641021401 has 2 divisors, whose sum is σ = 641021402. Its totient is φ = 641021400.

The previous prime is 641021389. The next prime is 641021419. The reversal of 641021401 is 104120146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 340033600 + 300987801 = 18440^2 + 17349^2 .

It is a cyclic number.

It is not a de Polignac number, because 641021401 - 2⁵ = 641021369 is a prime.

It is not a weakly prime, because it can be changed into another prime (641021471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320510700 + 320510701.

It is an arithmetic number, because the mean of its divisors is an integer number (320510701).

Almost surely, 2^641021401 is an apocalyptic number.

It is an amenable number.

641021401 is a deficient number, since it is larger than the sum of its proper divisors (1).

641021401 is an equidigital number, since it uses as much as digits as its factorization.

641021401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 641021401 is about 25318.4004431560. The cubic root of 641021401 is about 862.2320785420.

Adding to 641021401 its reverse (104120146), we get a palindrome (745141547).

The spelling of 641021401 in words is "six hundred forty-one million, twenty-one thousand, four hundred one".