21671441 has 8 divisors (see below), whose sum is σ = 24191904. Its totient is φ = 19242720.

The previous prime is 21671431. The next prime is 21671471. The reversal of 21671441 is 14417612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21671441 - 2¹⁰ = 21670417 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21671441.

It is not an unprimeable number, because it can be changed into a prime (21671431) 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 7 ways as a sum of consecutive naturals, for example, 22436 + ... + 23381.

It is an arithmetic number, because the mean of its divisors is an integer number (3023988).

Almost surely, 2^21671441 is an apocalyptic number.

It is an amenable number.

21671441 is a deficient number, since it is larger than the sum of its proper divisors (2520463).

21671441 is a wasteful number, since it uses less digits than its factorization.

21671441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45871.

The product of its digits is 1344, while the sum is 26.

The square root of 21671441 is about 4655.2594986746. The cubic root of 21671441 is about 278.8020289376.

The spelling of 21671441 in words is "twenty-one million, six hundred seventy-one thousand, four hundred forty-one".