21133013 has 6 divisors (see below), whose sum is σ = 23228982. Its totient is φ = 19211720.

The previous prime is 21133009. The next prime is 21133027. The reversal of 21133013 is 31033112.

It can be written as a sum of positive squares in only one way, i.e., 10745284 + 10387729 = 3278^2 + 3223^2 .

It is not a de Polignac number, because 21133013 - 2² = 21133009 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 87206 + ... + 87447.

It is an arithmetic number, because the mean of its divisors is an integer number (3871497).

Almost surely, 2^21133013 is an apocalyptic number.

It is an amenable number.

21133013 is a deficient number, since it is larger than the sum of its proper divisors (2095969).

21133013 is a wasteful number, since it uses less digits than its factorization.

21133013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174675 (or 174664 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 21133013 is about 4597.0656945491. The cubic root of 21133013 is about 276.4736885911.

Adding to 21133013 its reverse (31033112), we get a palindrome (52166125).

Subtracting 21133013 from its reverse (31033112), we obtain a palindrome (9900099).

The spelling of 21133013 in words is "twenty-one million, one hundred thirty-three thousand, thirteen".