21113053 has 4 divisors (see below), whose sum is σ = 22737148. Its totient is φ = 19488960.

The previous prime is 21113041. The next prime is 21113069. The reversal of 21113053 is 35031112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11546404 + 9566649 = 3398^2 + 3093^2 .

It is a cyclic number.

It is not a de Polignac number, because 21113053 - 2²¹ = 19015901 is a prime.

It is a super-2 number, since 2×21113053² = 891522013961618, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113023) 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 3 ways as a sum of consecutive naturals, for example, 812028 + ... + 812053.

It is an arithmetic number, because the mean of its divisors is an integer number (5684287).

Almost surely, 2^21113053 is an apocalyptic number.

It is an amenable number.

21113053 is a deficient number, since it is larger than the sum of its proper divisors (1624095).

21113053 is a wasteful number, since it uses less digits than its factorization.

21113053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1624094.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 21113053 is about 4594.8942316445. The cubic root of 21113053 is about 276.3866186103.

Adding to 21113053 its reverse (35031112), we get a palindrome (56144165).

The spelling of 21113053 in words is "twenty-one million, one hundred thirteen thousand, fifty-three".