21980228 has 12 divisors (see below), whose sum is σ = 38759952. Its totient is φ = 10905960.

The previous prime is 21980197. The next prime is 21980243. The reversal of 21980228 is 82208912.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21980194 and 21980203.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 20450 + ... + 21497.

It is an arithmetic number, because the mean of its divisors is an integer number (3229996).

Almost surely, 2^21980228 is an apocalyptic number.

It is an amenable number.

21980228 is a deficient number, since it is larger than the sum of its proper divisors (16779724).

21980228 is a wasteful number, since it uses less digits than its factorization.

21980228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42082 (or 42080 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 21980228 is about 4688.3075837662. The cubic root of 21980228 is about 280.1199656004.

The spelling of 21980228 in words is "twenty-one million, nine hundred eighty thousand, two hundred twenty-eight".