21489041 has 4 divisors (see below), whose sum is σ = 24558912. Its totient is φ = 18419172.

The previous prime is 21489031. The next prime is 21489047. The reversal of 21489041 is 14098412.

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 21489041 - 2¹⁴ = 21472657 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21488995 and 21489013.

It is not an unprimeable number, because it can be changed into a prime (21489047) 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, 1534925 + ... + 1534938.

It is an arithmetic number, because the mean of its divisors is an integer number (6139728).

Almost surely, 2^21489041 is an apocalyptic number.

It is an amenable number.

21489041 is a deficient number, since it is larger than the sum of its proper divisors (3069871).

21489041 is an equidigital number, since it uses as much as digits as its factorization.

21489041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3069870.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 21489041 is about 4635.6273577586. The cubic root of 21489041 is about 278.0176351320.

The spelling of 21489041 in words is "twenty-one million, four hundred eighty-nine thousand, forty-one".