21120020020001 has 16 divisors (see below), whose sum is σ = 24676235316096. Its totient is φ = 17702516532096.

The previous prime is 21120020019983. The next prime is 21120020020027. The reversal of 21120020020001 is 10002002002112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21120020020001 - 2³⁸ = 20845142113057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21120020020301) 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, 164286206 + ... + 164414711.

It is an arithmetic number, because the mean of its divisors is an integer number (1542264707256).

Almost surely, 2^{21120020020001} is an apocalyptic number.

It is an amenable number.

21120020020001 is a deficient number, since it is larger than the sum of its proper divisors (3556215296095).

21120020020001 is a wasteful number, since it uses less digits than its factorization.

21120020020001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328701128.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21120020020001 its reverse (10002002002112), we get a palindrome (31122022022113).

The spelling of 21120020020001 in words is "twenty-one trillion, one hundred twenty billion, twenty million, twenty thousand, one".