21556914 has 8 divisors (see below), whose sum is σ = 43113840. Its totient is φ = 7185636.

The previous prime is 21556907. The next prime is 21556921. The reversal of 21556914 is 41965512.

It is an interprime number because it is at equal distance from previous prime (21556907) and next prime (21556921).

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

21556914 is an admirable number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1796404 + ... + 1796415.

It is an arithmetic number, because the mean of its divisors is an integer number (5389230).

Almost surely, 2^21556914 is an apocalyptic number.

21556914 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21556914 is a wasteful number, since it uses less digits than its factorization.

21556914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3592824.

The product of its digits is 10800, while the sum is 33.

The square root of 21556914 is about 4642.9423860307. The cubic root of 21556914 is about 278.3100331490.

The spelling of 21556914 in words is "twenty-one million, five hundred fifty-six thousand, nine hundred fourteen".