21340541 has 8 divisors (see below), whose sum is σ = 22171968. Its totient is φ = 20524000.

The previous prime is 21340537. The next prime is 21340547. The reversal of 21340541 is 14504312.

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 21340541 - 2² = 21340537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21340547) 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 7 ways as a sum of consecutive naturals, for example, 755 + ... + 6576.

It is an arithmetic number, because the mean of its divisors is an integer number (2771496).

Almost surely, 2^21340541 is an apocalyptic number.

It is an amenable number.

21340541 is a deficient number, since it is larger than the sum of its proper divisors (831427).

21340541 is an equidigital number, since it uses as much as digits as its factorization.

21340541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7443.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 21340541 is about 4619.5823404286. The cubic root of 21340541 is about 277.3757407042.

Adding to 21340541 its reverse (14504312), we get a palindrome (35844853).

The spelling of 21340541 in words is "twenty-one million, three hundred forty thousand, five hundred forty-one".