643105522550 has 24 divisors (see below), whose sum is σ = 1225351306872. Its totient is φ = 250968008000.

The previous prime is 643105522513. The next prime is 643105522559. The reversal of 643105522550 is 55225501346.

643105522550 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643105522559) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156852956 + ... + 156857055.

It is an arithmetic number, because the mean of its divisors is an integer number (51056304453).

Almost surely, 2^643105522550 is an apocalyptic number.

643105522550 is a deficient number, since it is larger than the sum of its proper divisors (582245784322).

643105522550 is a wasteful number, since it uses less digits than its factorization.

643105522550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313710064 (or 313710059 counting only the distinct ones).

The product of its (nonzero) digits is 180000, while the sum is 38.

The spelling of 643105522550 in words is "six hundred forty-three billion, one hundred five million, five hundred twenty-two thousand, five hundred fifty".