1647639929868 has 24 divisors (see below), whose sum is σ = 3856854892800. Its totient is φ = 547447349520.

The previous prime is 1647639929861. The next prime is 1647639929911. The reversal of 1647639929868 is 8689299367461.

It is a junction number, because it is equal to n+sod(n) for n = 1647639929793 and 1647639929802.

It is not an unprimeable number, because it can be changed into a prime (1647639929861) 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, 220741168 + ... + 220748631.

It is an arithmetic number, because the mean of its divisors is an integer number (160702287200).

Almost surely, 2^{1647639929868} is an apocalyptic number.

It is an amenable number.

1647639929868 is an abundant number, since it is smaller than the sum of its proper divisors (2209214962932).

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

1647639929868 is a wasteful number, since it uses less digits than its factorization.

1647639929868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441490117 (or 441490115 counting only the distinct ones).

The product of its digits is 1693052928, while the sum is 78.

The spelling of 1647639929868 in words is "one trillion, six hundred forty-seven billion, six hundred thirty-nine million, nine hundred twenty-nine thousand, eight hundred sixty-eight".