21011442 has 8 divisors (see below), whose sum is σ = 42022896. Its totient is φ = 7003812.

The previous prime is 21011423. The next prime is 21011447. The reversal of 21011442 is 24411012.

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

21011442 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21011447) 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, 1750948 + ... + 1750959.

It is an arithmetic number, because the mean of its divisors is an integer number (5252862).

Almost surely, 2^21011442 is an apocalyptic number.

21011442 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.

21011442 is a wasteful number, since it uses less digits than its factorization.

21011442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3501912.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 21011442 is about 4583.8239494989. The cubic root of 21011442 is about 275.9425158586.

Adding to 21011442 its reverse (24411012), we get a palindrome (45422454).

The spelling of 21011442 in words is "twenty-one million, eleven thousand, four hundred forty-two".