21253101221466 has 96 divisors (see below), whose sum is σ = 48714113448000. Its totient is φ = 6677996451840.

The previous prime is 21253101221453. The next prime is 21253101221489. The reversal of 21253101221466 is 66412210135212.

21253101221466 is a `hidden beast` number, since 2 + 12 + 53 + 10 + 122 + 1 + 466 = 666.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21253101221466.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 299942010 + ... + 300012858.

It is an arithmetic number, because the mean of its divisors is an integer number (507438681750).

Almost surely, 2^{21253101221466} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21253101221466, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24357056724000).

21253101221466 is an abundant number, since it is smaller than the sum of its proper divisors (27461012226534).

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

21253101221466 is a wasteful number, since it uses less digits than its factorization.

21253101221466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75244 (or 75241 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

Adding to 21253101221466 its reverse (66412210135212), we get a palindrome (87665311356678).

The spelling of 21253101221466 in words is "twenty-one trillion, two hundred fifty-three billion, one hundred one million, two hundred twenty-one thousand, four hundred sixty-six".