21211121100001 has 16 divisors (see below), whose sum is σ = 24737979024000. Its totient is φ = 18179507303664.

The previous prime is 21211121099957. The next prime is 21211121100067. The reversal of 21211121100001 is 10000112111212.

It is a happy number.

It is not a de Polignac number, because 21211121100001 - 2¹¹ = 21211121097953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21211121160001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1834971 + ... + 6766783.

It is an arithmetic number, because the mean of its divisors is an integer number (1546123689000).

Almost surely, 2^{21211121100001} is an apocalyptic number.

It is an amenable number.

21211121100001 is a deficient number, since it is larger than the sum of its proper divisors (3526857923999).

21211121100001 is an equidigital number, since it uses as much as digits as its factorization.

21211121100001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4944373 (or 4944359 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21211121100001 its reverse (10000112111212), we get a palindrome (31211233211213).

The spelling of 21211121100001 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-one million, one hundred thousand, one".