21752222 has 8 divisors (see below), whose sum is σ = 33424272. Its totient is φ = 10610800.

The previous prime is 21752221. The next prime is 21752239. The reversal of 21752222 is 22225712.

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 (21752221) 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, 132554 + ... + 132717.

It is an arithmetic number, because the mean of its divisors is an integer number (4178034).

Almost surely, 2^21752222 is an apocalyptic number.

21752222 is a deficient number, since it is larger than the sum of its proper divisors (11672050).

21752222 is a wasteful number, since it uses less digits than its factorization.

21752222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265314.

The product of its digits is 1120, while the sum is 23.

The square root of 21752222 is about 4663.9277438657. The cubic root of 21752222 is about 279.1480139415.

Adding to 21752222 its reverse (22225712), we get a palindrome (43977934).

The spelling of 21752222 in words is "twenty-one million, seven hundred fifty-two thousand, two hundred twenty-two".