21081141 has 20 divisors (see below), whose sum is σ = 31655052. Its totient is φ = 13981248.

The previous prime is 21081131. The next prime is 21081143. The reversal of 21081141 is 14118012.

It can be written as a sum of positive squares in 2 ways, for example, as 2340900 + 18740241 = 1530^2 + 4329^2 .

It is not a de Polignac number, because 21081141 - 2¹⁰ = 21080117 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21081143) 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 19 ways as a sum of consecutive naturals, for example, 18315 + ... + 19431.

Almost surely, 2^21081141 is an apocalyptic number.

It is an amenable number.

21081141 is a deficient number, since it is larger than the sum of its proper divisors (10573911).

21081141 is a wasteful number, since it uses less digits than its factorization.

21081141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1362 (or 1353 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

The square root of 21081141 is about 4591.4203684699. The cubic root of 21081141 is about 276.2472972579.

Adding to 21081141 its reverse (14118012), we get a palindrome (35199153).

It can be divided in two parts, 2108 and 1141, that added together give a square (3249 = 57²).

The spelling of 21081141 in words is "twenty-one million, eighty-one thousand, one hundred forty-one".