21417580 has 24 divisors (see below), whose sum is σ = 46075680. Its totient is φ = 8357760.

The previous prime is 21417553. The next prime is 21417587. The reversal of 21417580 is 8571412.

It is not an unprimeable number, because it can be changed into a prime (21417587) 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, 12240 + ... + 13879.

It is an arithmetic number, because the mean of its divisors is an integer number (1919820).

Almost surely, 2^21417580 is an apocalyptic number.

21417580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21417580 is an abundant number, since it is smaller than the sum of its proper divisors (24658100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21417580 is a wasteful number, since it uses less digits than its factorization.

21417580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26169 (or 26167 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 21417580 is about 4627.9131366092. The cubic root of 21417580 is about 277.7091138135.

Adding to 21417580 its reverse (8571412), we get a palindrome (29988992).

The spelling of 21417580 in words is "twenty-one million, four hundred seventeen thousand, five hundred eighty".