21121210001011 has 4 divisors (see below), whose sum is σ = 21121219851112. Its totient is φ = 21121200150912.

The previous prime is 21121210001009. The next prime is 21121210001069. The reversal of 21121210001011 is 11010001212112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21121210001011 - 2¹ = 21121210001009 is a prime.

It is a super-2 number, since 2×21121210001011² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121210000982 and 21121210001000.

It is not an unprimeable number, because it can be changed into a prime (21121210061011) 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, 193326 + ... + 6502291.

It is an arithmetic number, because the mean of its divisors is an integer number (5280304962778).

Almost surely, 2^{21121210001011} is an apocalyptic number.

21121210001011 is a deficient number, since it is larger than the sum of its proper divisors (9850101).

21121210001011 is an equidigital number, since it uses as much as digits as its factorization.

21121210001011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9850100.

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

Adding to 21121210001011 its reverse (11010001212112), we get a palindrome (32131211213123).

The spelling of 21121210001011 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred ten million, one thousand, eleven".