21006183744 has 168 divisors, whose sum is σ = 74105333120. Its totient is φ = 5540078592.

The previous prime is 21006183721. The next prime is 21006183749. The reversal of 21006183744 is 44738160012.

21006183744 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 618 + 37 + 4 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21006183699 and 21006183708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21006183749) 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 23 ways as a sum of consecutive naturals, for example, 147964 + ... + 252795.

Almost surely, 2^21006183744 is an apocalyptic number.

21006183744 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21006183744 is an abundant number, since it is smaller than the sum of its proper divisors (53099149376).

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

21006183744 is a wasteful number, since it uses less digits than its factorization.

21006183744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400797 (or 400784 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 21006183744 in words is "twenty-one billion, six million, one hundred eighty-three thousand, seven hundred forty-four".