643348877 has 2 divisors, whose sum is σ = 643348878. Its totient is φ = 643348876.

The previous prime is 643348837. The next prime is 643348879. The reversal of 643348877 is 778843346.

643348877 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 448634761 + 194714116 = 21181^2 + 13954^2 .

It is a cyclic number.

It is not a de Polignac number, because 643348877 - 2⁶ = 643348813 is a prime.

It is a super-2 number, since 2×643348877² = 827795555074322258, which contains 22 as substring.

Together with 643348879, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643348879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321674438 + 321674439.

It is an arithmetic number, because the mean of its divisors is an integer number (321674439).

Almost surely, 2^643348877 is an apocalyptic number.

It is an amenable number.

643348877 is a deficient number, since it is larger than the sum of its proper divisors (1).

643348877 is an equidigital number, since it uses as much as digits as its factorization.

643348877 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2709504, while the sum is 50.

The square root of 643348877 is about 25364.3229162538. The cubic root of 643348877 is about 863.2743736993.

The spelling of 643348877 in words is "six hundred forty-three million, three hundred forty-eight thousand, eight hundred seventy-seven".