21802441 has 4 divisors (see below), whose sum is σ = 21822084. Its totient is φ = 21782800.

The previous prime is 21802439. The next prime is 21802453. The reversal of 21802441 is 14420812.

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 10106041 + 11696400 = 3179^2 + 3420^2 .

It is a cyclic number.

It is not a de Polignac number, because 21802441 - 2¹ = 21802439 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21802411) 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, 8050 + ... + 10411.

It is an arithmetic number, because the mean of its divisors is an integer number (5455521).

Almost surely, 2^21802441 is an apocalyptic number.

It is an amenable number.

21802441 is a deficient number, since it is larger than the sum of its proper divisors (19643).

21802441 is a wasteful number, since it uses less digits than its factorization.

21802441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19642.

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 21802441 is about 4669.3084070342. The cubic root of 21802441 is about 279.3626703232.

The spelling of 21802441 in words is "twenty-one million, eight hundred two thousand, four hundred forty-one".