21672011 has 2 divisors, whose sum is σ = 21672012. Its totient is φ = 21672010.

The previous prime is 21671999. The next prime is 21672023. The reversal of 21672011 is 11027612.

It is a balanced prime because it is at equal distance from previous prime (21671999) and next prime (21672023).

It is a cyclic number.

It is not a de Polignac number, because 21672011 - 2¹⁸ = 21409867 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21672041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10836005 + 10836006.

It is an arithmetic number, because the mean of its divisors is an integer number (10836006).

Almost surely, 2^21672011 is an apocalyptic number.

21672011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21672011 is an equidigital number, since it uses as much as digits as its factorization.

21672011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 21672011 is about 4655.3207193490. The cubic root of 21672011 is about 278.8044732569.

Adding to 21672011 its reverse (11027612), we get a palindrome (32699623).

It can be divided in two parts, 216 and 72011, that added together give a palindrome (72227).

The spelling of 21672011 in words is "twenty-one million, six hundred seventy-two thousand, eleven".