20111021211001 has 32 divisors (see below), whose sum is σ = 24359450572800. Its totient is φ = 16219021547520.

The previous prime is 20111021210999. The next prime is 20111021211011. The reversal of 20111021211001 is 10011212011102.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20111021211001 - 2¹ = 20111021210999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20111021211011) 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, 30216516 + ... + 30874906.

It is an arithmetic number, because the mean of its divisors is an integer number (761232830400).

Almost surely, 2^{20111021211001} is an apocalyptic number.

It is an amenable number.

20111021211001 is a deficient number, since it is larger than the sum of its proper divisors (4248429361799).

20111021211001 is a wasteful number, since it uses less digits than its factorization.

20111021211001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659989.

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

Adding to 20111021211001 its reverse (10011212011102), we get a palindrome (30122233222103).

The spelling of 20111021211001 in words is "twenty trillion, one hundred eleven billion, twenty-one million, two hundred eleven thousand, one".