21342072 has 64 divisors (see below), whose sum is σ = 57002400. Its totient is φ = 6658560.

The previous prime is 21342071. The next prime is 21342119. The reversal of 21342072 is 27024312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21342071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117822 + ... + 118002.

Almost surely, 2^21342072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21342072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28501200).

21342072 is an abundant number, since it is smaller than the sum of its proper divisors (35660328).

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

21342072 is a wasteful number, since it uses less digits than its factorization.

21342072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 21342072 is about 4619.7480450778. The cubic root of 21342072 is about 277.3823736523.

Adding to 21342072 its reverse (27024312), we get a palindrome (48366384).

The spelling of 21342072 in words is "twenty-one million, three hundred forty-two thousand, seventy-two".