21359228 has 12 divisors (see below), whose sum is σ = 40776792. Its totient is φ = 9708720.

The previous prime is 21359209. The next prime is 21359243. The reversal of 21359228 is 82295312.

It is a happy number.

It is a super-3 number, since 3×21359228³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21359194 and 21359203.

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, 242675 + ... + 242762.

It is an arithmetic number, because the mean of its divisors is an integer number (3398066).

Almost surely, 2^21359228 is an apocalyptic number.

It is an amenable number.

21359228 is a deficient number, since it is larger than the sum of its proper divisors (19417564).

21359228 is a wasteful number, since it uses less digits than its factorization.

21359228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485452 (or 485450 counting only the distinct ones).

The product of its digits is 8640, while the sum is 32.

The square root of 21359228 is about 4621.6044832937. The cubic root of 21359228 is about 277.4566791125.

The spelling of 21359228 in words is "twenty-one million, three hundred fifty-nine thousand, two hundred twenty-eight".