21056707662144 has 448 divisors, whose sum is σ = 69905303562240. Its totient is φ = 5434246471680.

The previous prime is 21056707662139. The next prime is 21056707662157. The reversal of 21056707662144 is 44126670765012.

It is a tau number, because it is divible by the number of its divisors (448).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4268537502 + ... + 4268542434.

Almost surely, 2^{21056707662144} is an apocalyptic number.

21056707662144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21056707662144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34952651781120).

21056707662144 is an abundant number, since it is smaller than the sum of its proper divisors (48848595900096).

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

21056707662144 is a wasteful number, since it uses less digits than its factorization.

21056707662144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6758 (or 6748 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 51.

The spelling of 21056707662144 in words is "twenty-one trillion, fifty-six billion, seven hundred seven million, six hundred sixty-two thousand, one hundred forty-four".