21881141 has 4 divisors (see below), whose sum is σ = 23032800. Its totient is φ = 20729484.

The previous prime is 21881137. The next prime is 21881143. The reversal of 21881141 is 14118812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21881141 - 2² = 21881137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21881141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21881143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 575801 + ... + 575838.

It is an arithmetic number, because the mean of its divisors is an integer number (5758200).

Almost surely, 2^21881141 is an apocalyptic number.

It is an amenable number.

21881141 is a deficient number, since it is larger than the sum of its proper divisors (1151659).

21881141 is a wasteful number, since it uses less digits than its factorization.

21881141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1151658.

The product of its digits is 512, while the sum is 26.

The square root of 21881141 is about 4677.7281879134. The cubic root of 21881141 is about 279.6984040005.

Adding to 21881141 its reverse (14118812), we get a palindrome (35999953).

It can be divided in two parts, 21881 and 141, that added together give a palindrome (22022).

The spelling of 21881141 in words is "twenty-one million, eight hundred eighty-one thousand, one hundred forty-one".