20101021010111 has 4 divisors (see below), whose sum is σ = 20101556118912. Its totient is φ = 20100485901312.

The previous prime is 20101021010093. The next prime is 20101021010113. The reversal of 20101021010111 is 11101012010102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20101021010111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20101021010092 and 20101021010101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101021010113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 267498050 + ... + 267573183.

It is an arithmetic number, because the mean of its divisors is an integer number (5025389029728).

Almost surely, 2^{20101021010111} is an apocalyptic number.

20101021010111 is a deficient number, since it is larger than the sum of its proper divisors (535108801).

20101021010111 is an equidigital number, since it uses as much as digits as its factorization.

20101021010111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535108800.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 20101021010111 its reverse (11101012010102), we get a palindrome (31202033020213).

Subtracting from 20101021010111 its reverse (11101012010102), we obtain a palindrome (9000009000009).

The spelling of 20101021010111 in words is "twenty trillion, one hundred one billion, twenty-one million, ten thousand, one hundred eleven".