643106752878 has 16 divisors (see below), whose sum is σ = 1317584567376. Its totient is φ = 209140407360.

The previous prime is 643106752843. The next prime is 643106753041. The reversal of 643106752878 is 878257601346.

643106752878 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×643106752878² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1307127301 + ... + 1307127792.

It is an arithmetic number, because the mean of its divisors is an integer number (82349035461).

Almost surely, 2^643106752878 is an apocalyptic number.

643106752878 is an abundant number, since it is smaller than the sum of its proper divisors (674477814498).

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

643106752878 is a wasteful number, since it uses less digits than its factorization.

643106752878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2614255139.

The product of its (nonzero) digits is 13547520, while the sum is 57.

The spelling of 643106752878 in words is "six hundred forty-three billion, one hundred six million, seven hundred fifty-two thousand, eight hundred seventy-eight".