643474787922 has 54 divisors (see below), whose sum is σ = 1414639719831. Its totient is φ = 211391176920.

The previous prime is 643474787911. The next prime is 643474787927. The reversal of 643474787922 is 229787474346.

643474787922 is a `hidden beast` number, since 6 + 4 + 3 + 474 + 78 + 7 + 92 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 321737393961 + 321737393961 = 567219^2 + 567219^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=567219.

It is a self number, because there is not a number n which added to its sum of digits gives 643474787922.

It is not an unprimeable number, because it can be changed into a prime (643474787927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 241633963 + ... + 241636625.

Almost surely, 2^643474787922 is an apocalyptic number.

643474787922 is an abundant number, since it is smaller than the sum of its proper divisors (771164931909).

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

643474787922 is an frugal number, since it uses more digits than its factorization.

643474787922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5476 (or 2739 counting only the distinct ones).

The product of its digits is 113799168, while the sum is 63.

The spelling of 643474787922 in words is "six hundred forty-three billion, four hundred seventy-four million, seven hundred eighty-seven thousand, nine hundred twenty-two".