21911222 has 4 divisors (see below), whose sum is σ = 32866836. Its totient is φ = 10955610.

The previous prime is 21911221. The next prime is 21911231. The reversal of 21911222 is 22211912.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 21911194 and 21911203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21911221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5477804 + ... + 5477807.

It is an arithmetic number, because the mean of its divisors is an integer number (8216709).

Almost surely, 2^21911222 is an apocalyptic number.

21911222 is a deficient number, since it is larger than the sum of its proper divisors (10955614).

21911222 is a wasteful number, since it uses less digits than its factorization.

21911222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10955613.

The product of its digits is 144, while the sum is 20.

The square root of 21911222 is about 4680.9424264778. The cubic root of 21911222 is about 279.8265166845.

The spelling of 21911222 in words is "twenty-one million, nine hundred eleven thousand, two hundred twenty-two".