21302272 has 44 divisors (see below), whose sum is σ = 43330896. Its totient is φ = 10465280.

The previous prime is 21302261. The next prime is 21302273. The reversal of 21302272 is 27220312.

It is not an unprimeable number, because it can be changed into a prime (21302273) 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, 72558 + ... + 72850.

Almost surely, 2^21302272 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 21302272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21665448).

21302272 is an abundant number, since it is smaller than the sum of its proper divisors (22028624).

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

21302272 is an equidigital number, since it uses as much as digits as its factorization.

21302272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384 (or 366 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 21302272 is about 4615.4384407118. The cubic root of 21302272 is about 277.2098398239.

Adding to 21302272 its reverse (27220312), we get a palindrome (48522584).

The spelling of 21302272 in words is "twenty-one million, three hundred two thousand, two hundred seventy-two".