641781980629 has 2 divisors, whose sum is σ = 641781980630. Its totient is φ = 641781980628.

The previous prime is 641781980597. The next prime is 641781980641. The reversal of 641781980629 is 926089187146.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 603887518404 + 37894462225 = 777102^2 + 194665^2 .

It is a cyclic number.

It is not a de Polignac number, because 641781980629 - 2⁵ = 641781980597 is a prime.

It is a super-2 number, since 2×641781980629² (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 (641781980129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320890990314 + 320890990315.

It is an arithmetic number, because the mean of its divisors is an integer number (320890990315).

Almost surely, 2^641781980629 is an apocalyptic number.

It is an amenable number.

641781980629 is a deficient number, since it is larger than the sum of its proper divisors (1).

641781980629 is an equidigital number, since it uses as much as digits as its factorization.

641781980629 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10450944, while the sum is 61.

The spelling of 641781980629 in words is "six hundred forty-one billion, seven hundred eighty-one million, nine hundred eighty thousand, six hundred twenty-nine".