21313234 has 4 divisors (see below), whose sum is σ = 31969854. Its totient is φ = 10656616.

The previous prime is 21313207. The next prime is 21313241. The reversal of 21313234 is 43231312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 12581209 + 8732025 = 3547^2 + 2955^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5328307 + ... + 5328310.

Almost surely, 2^21313234 is an apocalyptic number.

21313234 is a deficient number, since it is larger than the sum of its proper divisors (10656620).

21313234 is a wasteful number, since it uses less digits than its factorization.

21313234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10656619.

The product of its digits is 432, while the sum is 19.

The square root of 21313234 is about 4616.6258241274. The cubic root of 21313234 is about 277.2573817507.

Adding to 21313234 its reverse (43231312), we get a palindrome (64544546).

The spelling of 21313234 in words is "twenty-one million, three hundred thirteen thousand, two hundred thirty-four".