21020213011 has 6 divisors (see below), whose sum is σ = 24452084580. Its totient is φ = 18017325396.

The previous prime is 21020212973. The next prime is 21020213051. The reversal of 21020213011 is 11031202012.

It is not a de Polignac number, because 21020213011 - 2¹¹ = 21020210963 is a prime.

It is a super-2 number, since 2×21020213011² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21020212982 and 21020213000.

It is not an unprimeable number, because it can be changed into a prime (21020213051) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 214491921 + ... + 214492018.

It is an arithmetic number, because the mean of its divisors is an integer number (4075347430).

Almost surely, 2^21020213011 is an apocalyptic number.

21020213011 is a deficient number, since it is larger than the sum of its proper divisors (3431871569).

21020213011 is an equidigital number, since it uses as much as digits as its factorization.

21020213011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428983953 (or 428983946 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21020213011 its reverse (11031202012), we get a palindrome (32051415023).

The spelling of 21020213011 in words is "twenty-one billion, twenty million, two hundred thirteen thousand, eleven".