6619863681 has 6 divisors (see below), whose sum is σ = 9562025330. Its totient is φ = 4413242448.

The previous prime is 6619863671. The next prime is 6619863683. The reversal of 6619863681 is 1863689166.

It can be written as a sum of positive squares in only one way, i.e., 6465607281 + 154256400 = 80409^2 + 12420^2 .

It is not a de Polignac number, because 6619863681 - 2³⁰ = 5546121857 is a prime.

It is a super-2 number, since 2×6619863681² = 87645190310045739522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6619863683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 367770196 + ... + 367770213.

Almost surely, 2^6619863681 is an apocalyptic number.

It is an amenable number.

6619863681 is a deficient number, since it is larger than the sum of its proper divisors (2942161649).

6619863681 is a wasteful number, since it uses less digits than its factorization.

6619863681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 735540415 (or 735540412 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 54.

The square root of 6619863681 is about 81362.5447057797. The cubic root of 6619863681 is about 1877.6573810080.

The spelling of 6619863681 in words is "six billion, six hundred nineteen million, eight hundred sixty-three thousand, six hundred eighty-one".