21551214 has 8 divisors (see below), whose sum is σ = 43102440. Its totient is φ = 7183736.

The previous prime is 21551177. The next prime is 21551221. The reversal of 21551214 is 41215512.

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

21551214 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1795929 + ... + 1795940.

It is an arithmetic number, because the mean of its divisors is an integer number (5387805).

Almost surely, 2^21551214 is an apocalyptic number.

21551214 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.

21551214 is a wasteful number, since it uses less digits than its factorization.

21551214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3591874.

The product of its digits is 400, while the sum is 21.

The square root of 21551214 is about 4642.3285105645. The cubic root of 21551214 is about 278.2855010811.

Adding to 21551214 its reverse (41215512), we get a palindrome (62766726).

The spelling of 21551214 in words is "twenty-one million, five hundred fifty-one thousand, two hundred fourteen".