21338680 has 32 divisors (see below), whose sum is σ = 52377840. Its totient is φ = 7759360.

The previous prime is 21338671. The next prime is 21338683. The reversal of 21338680 is 8683312.

21338680 is nontrivially palindromic in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21338683) 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, 23809 + ... + 24688.

Almost surely, 2^21338680 is an apocalyptic number.

21338680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21338680 is an abundant number, since it is smaller than the sum of its proper divisors (31039160).

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

21338680 is a wasteful number, since it uses less digits than its factorization.

21338680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48519 (or 48515 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 21338680 is about 4619.3809109014. The cubic root of 21338680 is about 277.3676776275.

The spelling of 21338680 in words is "twenty-one million, three hundred thirty-eight thousand, six hundred eighty".