21011201100020 has 24 divisors (see below), whose sum is σ = 44131569872544. Its totient is φ = 8402947570976.

The previous prime is 21011201100013. The next prime is 21011201100023. The reversal of 21011201100020 is 2000110211012.

It is a junction number, because it is equal to n+sod(n) for n = 21011201099974 and 21011201100010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011201100023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95691914 + ... + 95911233.

It is an arithmetic number, because the mean of its divisors is an integer number (1838815411356).

Almost surely, 2^{21011201100020} is an apocalyptic number.

21011201100020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011201100020 is an abundant number, since it is smaller than the sum of its proper divisors (23120368772524).

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

21011201100020 is a wasteful number, since it uses less digits than its factorization.

21011201100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191608639 (or 191608637 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21011201100020 its reverse (2000110211012), we get a palindrome (23011311311032).

The spelling of 21011201100020 in words is "twenty-one trillion, eleven billion, two hundred one million, one hundred thousand, twenty".