21301645563136 has 72 divisors (see below), whose sum is σ = 42766530436224. Its totient is φ = 10589196226560.

The previous prime is 21301645563071. The next prime is 21301645563239. The reversal of 21301645563136 is 63136554610312.

It is a happy number.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51270345 + ... + 51684151.

It is an arithmetic number, because the mean of its divisors is an integer number (593979589392).

Almost surely, 2^{21301645563136} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21301645563136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21383265218112).

21301645563136 is an abundant number, since it is smaller than the sum of its proper divisors (21464884873088).

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

21301645563136 is an equidigital number, since it uses as much as digits as its factorization.

21301645563136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414987 (or 414973 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 46.

The spelling of 21301645563136 in words is "twenty-one trillion, three hundred one billion, six hundred forty-five million, five hundred sixty-three thousand, one hundred thirty-six".