20111221010101 has 16 divisors (see below), whose sum is σ = 21861055790784. Its totient is φ = 18390366618624.

The previous prime is 20111221010059. The next prime is 20111221010141. The reversal of 20111221010101 is 10101012211102.

It is a happy number.

It is not a de Polignac number, because 20111221010101 - 2¹³ = 20111221001909 is a prime.

It is a super-2 number, since 2×20111221010101² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111221010141) 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, 104544661 + ... + 104736853.

It is an arithmetic number, because the mean of its divisors is an integer number (1366315986924).

Almost surely, 2^{20111221010101} is an apocalyptic number.

It is an amenable number.

20111221010101 is a deficient number, since it is larger than the sum of its proper divisors (1749834780683).

20111221010101 is a wasteful number, since it uses less digits than its factorization.

20111221010101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267540.

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

Adding to 20111221010101 its reverse (10101012211102), we get a palindrome (30212233221203).

The spelling of 20111221010101 in words is "twenty trillion, one hundred eleven billion, two hundred twenty-one million, ten thousand, one hundred one".