641435755021 has 2 divisors, whose sum is σ = 641435755022. Its totient is φ = 641435755020.

The previous prime is 641435754991. The next prime is 641435755031. The reversal of 641435755021 is 120557534146.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 593469936900 + 47965818121 = 770370^2 + 219011^2 .

It is a cyclic number.

It is not a de Polignac number, because 641435755021 - 2⁷ = 641435754893 is a prime.

It is a super-2 number, since 2×641435755021² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641435755031) 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, 320717877510 + 320717877511.

It is an arithmetic number, because the mean of its divisors is an integer number (320717877511).

Almost surely, 2^641435755021 is an apocalyptic number.

It is an amenable number.

641435755021 is a deficient number, since it is larger than the sum of its proper divisors (1).

641435755021 is an equidigital number, since it uses as much as digits as its factorization.

641435755021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504000, while the sum is 43.

The spelling of 641435755021 in words is "six hundred forty-one billion, four hundred thirty-five million, seven hundred fifty-five thousand, twenty-one".