21030342 has 16 divisors (see below), whose sum is σ = 42653952. Its totient is φ = 6911240.

The previous prime is 21030337. The next prime is 21030379. The reversal of 21030342 is 24303012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24258 + ... + 25109.

It is an arithmetic number, because the mean of its divisors is an integer number (2665872).

Almost surely, 2^21030342 is an apocalyptic number.

21030342 is an abundant number, since it is smaller than the sum of its proper divisors (21623610).

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

21030342 is a wasteful number, since it uses less digits than its factorization.

21030342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49443.

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21030342 is about 4585.8850836016. The cubic root of 21030342 is about 276.0252287377.

Adding to 21030342 its reverse (24303012), we get a palindrome (45333354).

The spelling of 21030342 in words is "twenty-one million, thirty thousand, three hundred forty-two".