21001111020201 has 32 divisors (see below), whose sum is σ = 31467575043072. Its totient is φ = 12361454360640.

The previous prime is 21001111020199. The next prime is 21001111020221. The reversal of 21001111020201 is 10202011110012.

It is not a de Polignac number, because 21001111020201 - 2¹ = 21001111020199 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001111020221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28304566 + ... + 29037056.

It is an arithmetic number, because the mean of its divisors is an integer number (983361720096).

Almost surely, 2^{21001111020201} is an apocalyptic number.

It is an amenable number.

21001111020201 is a deficient number, since it is larger than the sum of its proper divisors (10466464022871).

21001111020201 is a wasteful number, since it uses less digits than its factorization.

21001111020201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 764493.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21001111020201 its reverse (10202011110012), we get a palindrome (31203122130213).

The spelling of 21001111020201 in words is "twenty-one trillion, one billion, one hundred eleven million, twenty thousand, two hundred one".