21628468592640 has 2688 divisors, whose sum is σ = 100115639930880. Its totient is φ = 4305167843328.

The previous prime is 21628468592639. The next prime is 21628468592641. The reversal of 21628468592640 is 4629586482612.

21628468592640 is a `hidden beast` number, since 2 + 1 + 6 + 28 + 468 + 5 + 92 + 64 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21628468592639) and next prime (21628468592641).

It is a tau number, because it is divible by the number of its divisors (2688).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21628468592641) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 296280391644 + ... + 296280391716.

It is an arithmetic number, because the mean of its divisors is an integer number (37245401760).

Almost surely, 2^{21628468592640} is an apocalyptic number.

21628468592640 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 21628468592640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50057819965440).

21628468592640 is an abundant number, since it is smaller than the sum of its proper divisors (78487171338240).

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

21628468592640 is an frugal number, since it uses more digits than its factorization.

21628468592640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 79626240, while the sum is 63.

The spelling of 21628468592640 in words is "twenty-one trillion, six hundred twenty-eight billion, four hundred sixty-eight million, five hundred ninety-two thousand, six hundred forty".