643198420429 has 2 divisors, whose sum is σ = 643198420430. Its totient is φ = 643198420428.

The previous prime is 643198420343. The next prime is 643198420457. The reversal of 643198420429 is 924024891346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 622360054404 + 20838366025 = 788898^2 + 144355^2 .

It is a cyclic number.

It is not a de Polignac number, because 643198420429 - 2⁷ = 643198420301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643198420829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321599210214 + 321599210215.

It is an arithmetic number, because the mean of its divisors is an integer number (321599210215).

Almost surely, 2^643198420429 is an apocalyptic number.

It is an amenable number.

643198420429 is a deficient number, since it is larger than the sum of its proper divisors (1).

643198420429 is an equidigital number, since it uses as much as digits as its factorization.

643198420429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2985984, while the sum is 52.

The spelling of 643198420429 in words is "six hundred forty-three billion, one hundred ninety-eight million, four hundred twenty thousand, four hundred twenty-nine".