21102441 has 4 divisors (see below), whose sum is σ = 28136592. Its totient is φ = 14068292.

The previous prime is 21102439. The next prime is 21102451. The reversal of 21102441 is 14420112.

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 21102441 - 2¹ = 21102439 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21102441.

It is not an unprimeable number, because it can be changed into a prime (21102421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3517071 + ... + 3517076.

It is an arithmetic number, because the mean of its divisors is an integer number (7034148).

Almost surely, 2^21102441 is an apocalyptic number.

It is an amenable number.

21102441 is a deficient number, since it is larger than the sum of its proper divisors (7034151).

21102441 is an equidigital number, since it uses as much as digits as its factorization.

21102441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7034150.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 21102441 is about 4593.7393265182. The cubic root of 21102441 is about 276.3403043494.

Adding to 21102441 its reverse (14420112), we get a palindrome (35522553).

The spelling of 21102441 in words is "twenty-one million, one hundred two thousand, four hundred forty-one".