5681551866 has 32 divisors (see below), whose sum is σ = 11416749120. Its totient is φ = 1884927744.

The previous prime is 5681551819. The next prime is 5681551867. The reversal of 5681551866 is 6681551865.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (5681551867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1772221 + ... + 1775423.

It is an arithmetic number, because the mean of its divisors is an integer number (356773410).

Almost surely, 2^5681551866 is an apocalyptic number.

5681551866 is an abundant number, since it is smaller than the sum of its proper divisors (5735197254).

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

5681551866 is a wasteful number, since it uses less digits than its factorization.

5681551866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4510.

The product of its digits is 1728000, while the sum is 51.

The square root of 5681551866 is about 75376.0695844510. The cubic root of 5681551866 is about 1784.3867588765.

Subtracting 5681551866 from its reverse (6681551865), we obtain a palindrome (999999999).

The spelling of 5681551866 in words is "five billion, six hundred eighty-one million, five hundred fifty-one thousand, eight hundred sixty-six".