21010011 has 24 divisors (see below), whose sum is σ = 32478144. Its totient is φ = 11978880.

The previous prime is 21009997. The next prime is 21010013. The reversal of 21010011 is 11001012.

It is not a de Polignac number, because 21010011 - 2⁷ = 21009883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21010013) 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 in 23 ways as a sum of consecutive naturals, for example, 8436 + ... + 10638.

It is an arithmetic number, because the mean of its divisors is an integer number (1353256).

Almost surely, 2^21010011 is an apocalyptic number.

21010011 is a deficient number, since it is larger than the sum of its proper divisors (11468133).

21010011 is a wasteful number, since it uses less digits than its factorization.

21010011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2251 (or 2234 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 6.

The square root of 21010011 is about 4583.6678544589. The cubic root of 21010011 is about 275.9362512924.

Adding to 21010011 its reverse (11001012), we get a palindrome (32011023).

Multiplying 21010011 by its reverse (11001012), we get a palindrome (231131383131132).

The spelling of 21010011 in words is "twenty-one million, ten thousand, eleven".