21825557737868 has 24 divisors (see below), whose sum is σ = 38818578966384. Its totient is φ = 10735911576000.

The previous prime is 21825557737861. The next prime is 21825557737889. The reversal of 21825557737868 is 86873775552812.

It is a junction number, because it is equal to n+sod(n) for n = 21825557737795 and 21825557737804.

It is not an unprimeable number, because it can be changed into a prime (21825557737861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 171986438 + ... + 172113293.

It is an arithmetic number, because the mean of its divisors is an integer number (1617440790266).

Almost surely, 2^{21825557737868} is an apocalyptic number.

It is an amenable number.

21825557737868 is a deficient number, since it is larger than the sum of its proper divisors (16993021228516).

21825557737868 is a wasteful number, since it uses less digits than its factorization.

21825557737868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344099993 (or 344099991 counting only the distinct ones).

The product of its digits is 1580544000, while the sum is 74.

The spelling of 21825557737868 in words is "twenty-one trillion, eight hundred twenty-five billion, five hundred fifty-seven million, seven hundred thirty-seven thousand, eight hundred sixty-eight".