21121101211011 has 4 divisors (see below), whose sum is σ = 28161468281352. Its totient is φ = 14080734140672.

The previous prime is 21121101210997. The next prime is 21121101211033. The reversal of 21121101211011 is 11011210112112.

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

It is a cyclic number.

It is not a de Polignac number, because 21121101211011 - 2¹³ = 21121101202819 is a prime.

It is a super-2 number, since 2×21121101211011² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121101211211) 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, 3520183535166 + ... + 3520183535171.

It is an arithmetic number, because the mean of its divisors is an integer number (7040367070338).

Almost surely, 2^{21121101211011} is an apocalyptic number.

21121101211011 is a deficient number, since it is larger than the sum of its proper divisors (7040367070341).

21121101211011 is an equidigital number, since it uses as much as digits as its factorization.

21121101211011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7040367070340.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21121101211011 its reverse (11011210112112), we get a palindrome (32132311323123).

The spelling of 21121101211011 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred one million, two hundred eleven thousand, eleven".