21040011053 has 16 divisors (see below), whose sum is σ = 22424080176. Its totient is φ = 19672396800.

The previous prime is 21040011049. The next prime is 21040011059. The reversal of 21040011053 is 35011004012.

It can be written as a sum of positive squares in 8 ways, for example, as 3678786409 + 17361224644 = 60653^2 + 131762^2 .

It is a cyclic number.

It is not a de Polignac number, because 21040011053 - 2² = 21040011049 is a prime.

It is a super-2 number, since 2×21040011053² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040011059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5683103 + ... + 5686803.

It is an arithmetic number, because the mean of its divisors is an integer number (1401505011).

Almost surely, 2^21040011053 is an apocalyptic number.

It is an amenable number.

21040011053 is a deficient number, since it is larger than the sum of its proper divisors (1384069123).

21040011053 is a wasteful number, since it uses less digits than its factorization.

21040011053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5824.

The product of its (nonzero) digits is 120, while the sum is 17.

Adding to 21040011053 its reverse (35011004012), we get a palindrome (56051015065).

The spelling of 21040011053 in words is "twenty-one billion, forty million, eleven thousand, fifty-three".