21113777804472 has 224 divisors, whose sum is σ = 60369305424480. Its totient is φ = 6918696622080.

The previous prime is 21113777804461. The next prime is 21113777804479. The reversal of 21113777804472 is 27440877731112.

21113777804472 is a `hidden beast` number, since 2 + 1 + 113 + 7 + 7 + 7 + 80 + 447 + 2 = 666.

It is a super-2 number, since 2×21113777804472² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113777804479) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 82167072 + ... + 82423632.

Almost surely, 2^{21113777804472} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21113777804472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30184652712240).

21113777804472 is an abundant number, since it is smaller than the sum of its proper divisors (39255527620008).

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

21113777804472 is a wasteful number, since it uses less digits than its factorization.

21113777804472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256825 (or 256806 counting only the distinct ones).

The product of its (nonzero) digits is 3687936, while the sum is 54.

The spelling of 21113777804472 in words is "twenty-one trillion, one hundred thirteen billion, seven hundred seventy-seven million, eight hundred four thousand, four hundred seventy-two".