21461443645620 has 192 divisors, whose sum is σ = 66201773654016. Its totient is φ = 5151455262720.

The previous prime is 21461443645597. The next prime is 21461443645639. The reversal of 21461443645620 is 2654634416412.

It is a super-2 number, since 2×21461443645620² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21461443645620.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 512344317 + ... + 512386203.

It is an arithmetic number, because the mean of its divisors is an integer number (344800904448).

Almost surely, 2^{21461443645620} is an apocalyptic number.

21461443645620 is a gapful number since it is divisible by the number (20) 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 21461443645620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33100886827008).

21461443645620 is an abundant number, since it is smaller than the sum of its proper divisors (44740330008396).

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

21461443645620 is a wasteful number, since it uses less digits than its factorization.

21461443645620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49550 (or 49548 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 48.

The spelling of 21461443645620 in words is "twenty-one trillion, four hundred sixty-one billion, four hundred forty-three million, six hundred forty-five thousand, six hundred twenty".