21141811 has 4 divisors (see below), whose sum is σ = 21264192. Its totient is φ = 21019432.

The previous prime is 21141803. The next prime is 21141821. The reversal of 21141811 is 11814112.

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

It is a cyclic number.

It is not a de Polignac number, because 21141811 - 2³ = 21141803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21141821) 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, 60931 + ... + 61276.

It is an arithmetic number, because the mean of its divisors is an integer number (5316048).

Almost surely, 2^21141811 is an apocalyptic number.

21141811 is a deficient number, since it is larger than the sum of its proper divisors (122381).

21141811 is a wasteful number, since it uses less digits than its factorization.

21141811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122380.

The product of its digits is 64, while the sum is 19.

The square root of 21141811 is about 4598.0225097318. The cubic root of 21141811 is about 276.5120500249.

Adding to 21141811 its reverse (11814112), we get a palindrome (32955923).

It can be divided in two parts, 21141 and 811, that added together give a cube (21952 = 28³).

The spelling of 21141811 in words is "twenty-one million, one hundred forty-one thousand, eight hundred eleven".