643244542042 has 32 divisors (see below), whose sum is σ = 1001259926784. Its totient is φ = 309749832000.

The previous prime is 643244542001. The next prime is 643244542117. The reversal of 643244542042 is 240245442346.

It is a junction number, because it is equal to n+sod(n) for n = 643244541986 and 643244542004.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1339692 + ... + 1755352.

It is an arithmetic number, because the mean of its divisors is an integer number (31289372712).

Almost surely, 2^643244542042 is an apocalyptic number.

643244542042 is a deficient number, since it is larger than the sum of its proper divisors (358015384742).

643244542042 is a wasteful number, since it uses less digits than its factorization.

643244542042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415974.

The product of its (nonzero) digits is 737280, while the sum is 40.

Adding to 643244542042 its reverse (240245442346), we get a palindrome (883489984388).

The spelling of 643244542042 in words is "six hundred forty-three billion, two hundred forty-four million, five hundred forty-two thousand, forty-two".