21436272 has 160 divisors (see below), whose sum is σ = 72495360. Its totient is φ = 5978880.

The previous prime is 21436271. The next prime is 21436301. The reversal of 21436272 is 27263412.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436271) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61603 + ... + 61949.

It is an arithmetic number, because the mean of its divisors is an integer number (453096).

Almost surely, 2^21436272 is an apocalyptic number.

21436272 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21436272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36247680).

21436272 is an abundant number, since it is smaller than the sum of its proper divisors (51059088).

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

21436272 is a wasteful number, since it uses less digits than its factorization.

21436272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388 (or 376 counting only the distinct ones).

The product of its digits is 4032, while the sum is 27.

The square root of 21436272 is about 4629.9321809288. The cubic root of 21436272 is about 277.7898796979.

Adding to 21436272 its reverse (27263412), we get a palindrome (48699684).

The spelling of 21436272 in words is "twenty-one million, four hundred thirty-six thousand, two hundred seventy-two".