21272152 has 32 divisors (see below), whose sum is σ = 43807680. Its totient is φ = 9603360.

The previous prime is 21272149. The next prime is 21272177. The reversal of 21272152 is 25127212.

It is a super-2 number, since 2×21272152² = 905008901422208, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13603 + ... + 15085.

It is an arithmetic number, because the mean of its divisors is an integer number (1368990).

Almost surely, 2^21272152 is an apocalyptic number.

21272152 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 21272152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21903840).

21272152 is an abundant number, since it is smaller than the sum of its proper divisors (22535528).

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

21272152 is a wasteful number, since it uses less digits than its factorization.

21272152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1663 (or 1659 counting only the distinct ones).

The product of its digits is 560, while the sum is 22.

The square root of 21272152 is about 4612.1743245459. The cubic root of 21272152 is about 277.0791260873.

Adding to 21272152 its reverse (25127212), we get a palindrome (46399364).

The spelling of 21272152 in words is "twenty-one million, two hundred seventy-two thousand, one hundred fifty-two".