11101220021 has 4 divisors (see below), whose sum is σ = 11126977344. Its totient is φ = 11075462700.

The previous prime is 11101219991. The next prime is 11101220029. The reversal of 11101220021 is 12002210111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11101220021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11101219984 and 11101220011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11101220029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12878015 + ... + 12878876.

It is an arithmetic number, because the mean of its divisors is an integer number (2781744336).

Almost surely, 2^11101220021 is an apocalyptic number.

It is an amenable number.

11101220021 is a deficient number, since it is larger than the sum of its proper divisors (25757323).

11101220021 is an equidigital number, since it uses as much as digits as its factorization.

11101220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25757322.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 11101220021 its reverse (12002210111), we get a palindrome (23103430132).

The spelling of 11101220021 in words is "eleven billion, one hundred one million, two hundred twenty thousand, twenty-one".