21220222 has 8 divisors (see below), whose sum is σ = 31860216. Its totient is φ = 10600152.

The previous prime is 21220219. The next prime is 21220223. The reversal of 21220222 is 22202212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1948 + ... + 6799.

It is an arithmetic number, because the mean of its divisors is an integer number (3982527).

Almost surely, 2^21220222 is an apocalyptic number.

21220222 is a deficient number, since it is larger than the sum of its proper divisors (10639994).

21220222 is a wasteful number, since it uses less digits than its factorization.

21220222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9962.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 21220222 is about 4606.5412187454. The cubic root of 21220222 is about 276.8534720084.

Adding to 21220222 its reverse (22202212), we get a palindrome (43422434).

The spelling of 21220222 in words is "twenty-one million, two hundred twenty thousand, two hundred twenty-two".