21227442 has 8 divisors (see below), whose sum is σ = 42454896. Its totient is φ = 7075812.

The previous prime is 21227419. The next prime is 21227447. The reversal of 21227442 is 24472212.

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

21227442 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21227447) 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, 1768948 + ... + 1768959.

It is an arithmetic number, because the mean of its divisors is an integer number (5306862).

Almost surely, 2^21227442 is an apocalyptic number.

21227442 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21227442 is a wasteful number, since it uses less digits than its factorization.

21227442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3537912.

The product of its digits is 1792, while the sum is 24.

The square root of 21227442 is about 4607.3248203269. The cubic root of 21227442 is about 276.8848674608.

Adding to 21227442 its reverse (24472212), we get a palindrome (45699654).

The spelling of 21227442 in words is "twenty-one million, two hundred twenty-seven thousand, four hundred forty-two".