21011121112220 has 48 divisors (see below), whose sum is σ = 45161464988640. Its totient is φ = 8206816859136.

The previous prime is 21011121112213. The next prime is 21011121112259. The reversal of 21011121112220 is 2221112111012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 224 + ... + 6482456.

It is an arithmetic number, because the mean of its divisors is an integer number (940863853930).

Almost surely, 2^{21011121112220} is an apocalyptic number.

21011121112220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011121112220 is an abundant number, since it is smaller than the sum of its proper divisors (24150343876420).

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

21011121112220 is a wasteful number, since it uses less digits than its factorization.

21011121112220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6486054 (or 6486052 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21011121112220 its reverse (2221112111012), we get a palindrome (23232233223232).

The spelling of 21011121112220 in words is "twenty-one trillion, eleven billion, one hundred twenty-one million, one hundred twelve thousand, two hundred twenty".