21106506201600 has 240 divisors, whose sum is σ = 69789750795072. Its totient is φ = 5623095951360.

The previous prime is 21106506201523. The next prime is 21106506201601. The reversal of 21106506201600 is 610260560112.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (21106506201601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40560664 + ... + 41077736.

Almost surely, 2^{21106506201600} is an apocalyptic number.

21106506201600 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 21106506201600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34894875397536).

21106506201600 is an abundant number, since it is smaller than the sum of its proper divisors (48683244593472).

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

21106506201600 is a wasteful number, since it uses less digits than its factorization.

21106506201600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518167 (or 518146 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

Adding to 21106506201600 its reverse (610260560112), we get a palindrome (21716766761712).

The spelling of 21106506201600 in words is "twenty-one trillion, one hundred six billion, five hundred six million, two hundred one thousand, six hundred".