21313204 has 24 divisors (see below), whose sum is σ = 40805856. Its totient is φ = 9660000.

The previous prime is 21313199. The next prime is 21313207. The reversal of 21313204 is 40231312.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21313207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30054 + ... + 30754.

It is an arithmetic number, because the mean of its divisors is an integer number (1700244).

Almost surely, 2^21313204 is an apocalyptic number.

It is an amenable number.

21313204 is a deficient number, since it is larger than the sum of its proper divisors (19492652).

21313204 is a wasteful number, since it uses less digits than its factorization.

21313204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407 (or 1405 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21313204 is about 4616.6225750000. The cubic root of 21313204 is about 277.2572516637.

Adding to 21313204 its reverse (40231312), we get a palindrome (61544516).

It can be divided in two parts, 2131 and 3204, that added together give a palindrome (5335).

The spelling of 21313204 in words is "twenty-one million, three hundred thirteen thousand, two hundred four".