21033011 has 2 divisors, whose sum is σ = 21033012. Its totient is φ = 21033010.

The previous prime is 21033007. The next prime is 21033053. The reversal of 21033011 is 11033012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21033011 - 2² = 21033007 is a prime.

It is a super-2 number, since 2×21033011² = 884775103452242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21032983 and 21033001.

It is not a weakly prime, because it can be changed into another prime (21033071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516505 + 10516506.

It is an arithmetic number, because the mean of its divisors is an integer number (10516506).

Almost surely, 2^21033011 is an apocalyptic number.

21033011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033011 is an equidigital number, since it uses as much as digits as its factorization.

21033011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21033011 is about 4586.1760759918. The cubic root of 21033011 is about 276.0369052029.

Adding to 21033011 its reverse (11033012), we get a palindrome (32066023).

Subtracting from 21033011 its reverse (11033012), we obtain a palindrome (9999999).

The spelling of 21033011 in words is "twenty-one million, thirty-three thousand, eleven".