21672160 has 48 divisors (see below), whose sum is σ = 53902800. Its totient is φ = 8211456.

The previous prime is 21672151. The next prime is 21672181. The reversal of 21672160 is 6127612.

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, 525 + ... + 6604.

It is an arithmetic number, because the mean of its divisors is an integer number (1122975).

Almost surely, 2^21672160 is an apocalyptic number.

21672160 is a gapful number since it is divisible by the number (20) 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 21672160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26951400).

21672160 is an abundant number, since it is smaller than the sum of its proper divisors (32230640).

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

21672160 is a wasteful number, since it uses less digits than its factorization.

21672160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7163 (or 7155 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21672160 is about 4655.3367225154. The cubic root of 21672160 is about 278.8051122035.

Adding to 21672160 its reverse (6127612), we get a palindrome (27799772).

The spelling of 21672160 in words is "twenty-one million, six hundred seventy-two thousand, one hundred sixty".