643543026 has 16 divisors (see below), whose sum is σ = 1470955584. Its totient is φ = 183869424.

The previous prime is 643543003. The next prime is 643543039. The reversal of 643543026 is 620345346.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 7661185 + ... + 7661268.

It is an arithmetic number, because the mean of its divisors is an integer number (91934724).

Almost surely, 2^643543026 is an apocalyptic number.

643543026 is an abundant number, since it is smaller than the sum of its proper divisors (827412558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643543026 is a wasteful number, since it uses less digits than its factorization.

643543026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15322465.

The product of its (nonzero) digits is 51840, while the sum is 33.

The square root of 643543026 is about 25368.1498339946. The cubic root of 643543026 is about 863.3612042436.

The spelling of 643543026 in words is "six hundred forty-three million, five hundred forty-three thousand, twenty-six".