21580041 has 24 divisors (see below), whose sum is σ = 33946464. Its totient is φ = 12156480.

The previous prime is 21580037. The next prime is 21580043. The reversal of 21580041 is 14008512.

It is not a de Polignac number, because 21580041 - 2² = 21580037 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21580043) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9726 + ... + 11736.

It is an arithmetic number, because the mean of its divisors is an integer number (1414436).

Almost surely, 2^21580041 is an apocalyptic number.

21580041 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21580041 is a deficient number, since it is larger than the sum of its proper divisors (12366423).

21580041 is a wasteful number, since it uses less digits than its factorization.

21580041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2101 (or 2094 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 21580041 is about 4645.4322726739. The cubic root of 21580041 is about 278.4095244421.

Adding to 21580041 its reverse (14008512), we get a palindrome (35588553).

The spelling of 21580041 in words is "twenty-one million, five hundred eighty thousand, forty-one".