21110055355440 has 240 divisors, whose sum is σ = 71068015418400. Its totient is φ = 5615589163008.

The previous prime is 21110055355427. The next prime is 21110055355463. The reversal of 21110055355440 is 4455355001112.

21110055355440 is a `hidden beast` number, since 2 + 1 + 1 + 10 + 0 + 5 + 53 + 554 + 40 = 666.

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 (36).

It is a junction number, because it is equal to n+sod(n) for n = 21110055355395 and 21110055355404.

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, 830797456 + ... + 830822864.

It is an arithmetic number, because the mean of its divisors is an integer number (296116730910).

Almost surely, 2^{21110055355440} is an apocalyptic number.

21110055355440 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 21110055355440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35534007709200).

21110055355440 is an abundant number, since it is smaller than the sum of its proper divisors (49957960062960).

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

21110055355440 is a wasteful number, since it uses less digits than its factorization.

21110055355440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28204 (or 28195 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 36.

The spelling of 21110055355440 in words is "twenty-one trillion, one hundred ten billion, fifty-five million, three hundred fifty-five thousand, four hundred forty".