21339180 has 96 divisors (see below), whose sum is σ = 68006400. Its totient is φ = 5552064.

The previous prime is 21339173. The next prime is 21339181. The reversal of 21339180 is 8193312.

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

It is not an unprimeable number, because it can be changed into a prime (21339181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22761 + ... + 23679.

It is an arithmetic number, because the mean of its divisors is an integer number (708400).

Almost surely, 2^21339180 is an apocalyptic number.

21339180 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 21339180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34003200).

21339180 is an abundant number, since it is smaller than the sum of its proper divisors (46667220).

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

21339180 is a wasteful number, since it uses less digits than its factorization.

21339180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980 (or 972 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 21339180 is about 4619.4350303906. The cubic root of 21339180 is about 277.3698440026.

It can be divided in two parts, 213 and 39180, that added together give a palindrome (39393).

The spelling of 21339180 in words is "twenty-one million, three hundred thirty-nine thousand, one hundred eighty".