643128029146 has 16 divisors (see below), whose sum is σ = 1035430948584. Its totient is φ = 298502613504.

The previous prime is 643128029143. The next prime is 643128029161. The reversal of 643128029146 is 641920821346.

It can be written as a sum of positive squares in 4 ways, for example, as 557419026025 + 85709003121 = 746605^2 + 292761^2 .

It is a super-2 number, since 2×643128029146² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643128029096 and 643128029105.

It is not an unprimeable number, because it can be changed into a prime (643128029143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129555945 + ... + 129560908.

Almost surely, 2^643128029146 is an apocalyptic number.

643128029146 is a deficient number, since it is larger than the sum of its proper divisors (392302919438).

643128029146 is a wasteful number, since it uses less digits than its factorization.

643128029146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259116945.

The product of its (nonzero) digits is 497664, while the sum is 46.

The spelling of 643128029146 in words is "six hundred forty-three billion, one hundred twenty-eight million, twenty-nine thousand, one hundred forty-six".