21180336 has 20 divisors (see below), whose sum is σ = 54715992. Its totient is φ = 7060096.

The previous prime is 21180331. The next prime is 21180343. The reversal of 21180336 is 63308112.

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

It is not an unprimeable number, because it can be changed into a prime (21180331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220581 + ... + 220676.

Almost surely, 2^21180336 is an apocalyptic number.

It is an amenable number.

21180336 is an abundant number, since it is smaller than the sum of its proper divisors (33535656).

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

21180336 is a wasteful number, since it uses less digits than its factorization.

21180336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441268 (or 441262 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21180336 is about 4602.2099039483. The cubic root of 21180336 is about 276.6799032392.

Adding to 21180336 its reverse (63308112), we get a palindrome (84488448).

The spelling of 21180336 in words is "twenty-one million, one hundred eighty thousand, three hundred thirty-six".