21143053 has 4 divisors (see below), whose sum is σ = 22386780. Its totient is φ = 19899328.

The previous prime is 21143051. The next prime is 21143069. The reversal of 21143053 is 35034112.

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 19695844 + 1447209 = 4438^2 + 1203^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143053 - 2¹ = 21143051 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21143053.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143051) 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, 621838 + ... + 621871.

It is an arithmetic number, because the mean of its divisors is an integer number (5596695).

Almost surely, 2^21143053 is an apocalyptic number.

It is an amenable number.

21143053 is a deficient number, since it is larger than the sum of its proper divisors (1243727).

21143053 is a wasteful number, since it uses less digits than its factorization.

21143053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1243726.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 21143053 is about 4598.1575658083. The cubic root of 21143053 is about 276.5174645917.

Adding to 21143053 its reverse (35034112), we get a palindrome (56177165).

It can be divided in two parts, 211 and 43053, that added together give a square (43264 = 208²).

The spelling of 21143053 in words is "twenty-one million, one hundred forty-three thousand, fifty-three".