21220111221582 has 128 divisors (see below), whose sum is σ = 55138059648000. Its totient is φ = 5403529450368.

The previous prime is 21220111221581. The next prime is 21220111221679. The reversal of 21220111221582 is 28512211102212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220111221581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12899248 + ... + 14450979.

It is an arithmetic number, because the mean of its divisors is an integer number (430766091000).

Almost surely, 2^{21220111221582} is an apocalyptic number.

21220111221582 is an abundant number, since it is smaller than the sum of its proper divisors (33917948426418).

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

21220111221582 is a wasteful number, since it uses less digits than its factorization.

21220111221582 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27350295 (or 27350281 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 30.

Adding to 21220111221582 its reverse (28512211102212), we get a palindrome (49732322323794).

The spelling of 21220111221582 in words is "twenty-one trillion, two hundred twenty billion, one hundred eleven million, two hundred twenty-one thousand, five hundred eighty-two".