21370272 has 192 divisors, whose sum is σ = 72576000. Its totient is φ = 5456640.

The previous prime is 21370249. The next prime is 21370333. The reversal of 21370272 is 27207312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 362179 + ... + 362237.

It is an arithmetic number, because the mean of its divisors is an integer number (378000).

Almost surely, 2^21370272 is an apocalyptic number.

21370272 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 21370272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36288000).

21370272 is an abundant number, since it is smaller than the sum of its proper divisors (51205728).

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

21370272 is a wasteful number, since it uses less digits than its factorization.

21370272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 21370272 is about 4622.7991520290. The cubic root of 21370272 is about 277.5044914458.

Adding to 21370272 its reverse (27207312), we get a palindrome (48577584).

The spelling of 21370272 in words is "twenty-one million, three hundred seventy thousand, two hundred seventy-two".