21011020111201 has 32 divisors (see below), whose sum is σ = 21928781721600. Its totient is φ = 20106803707200.

The previous prime is 21011020111163. The next prime is 21011020111217. The reversal of 21011020111201 is 10211102011012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21011020111201 - 2³⁷ = 20873581157729 is a prime.

It is a super-2 number, since 2×21011020111201² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011020111271) 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, 4490491380 + ... + 4490496058.

It is an arithmetic number, because the mean of its divisors is an integer number (685274428800).

Almost surely, 2^{21011020111201} is an apocalyptic number.

It is an amenable number.

21011020111201 is a deficient number, since it is larger than the sum of its proper divisors (917761610399).

21011020111201 is a wasteful number, since it uses less digits than its factorization.

21011020111201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6949.

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

Adding to 21011020111201 its reverse (10211102011012), we get a palindrome (31222122122213).

The spelling of 21011020111201 in words is "twenty-one trillion, eleven billion, twenty million, one hundred eleven thousand, two hundred one".