21343210 has 16 divisors (see below), whose sum is σ = 43906176. Its totient is φ = 7317648.

The previous prime is 21343187. The next prime is 21343243. The reversal of 21343210 is 1234312.

It is a happy number.

It is a super-2 number, since 2×21343210² = 911065226208200, which contains 22 as substring.

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, 152382 + ... + 152521.

It is an arithmetic number, because the mean of its divisors is an integer number (2744136).

Almost surely, 2^21343210 is an apocalyptic number.

21343210 is an abundant number, since it is smaller than the sum of its proper divisors (22562966).

21343210 is a wasteful number, since it uses less digits than its factorization.

21343210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304917.

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

The square root of 21343210 is about 4619.8712103261. The cubic root of 21343210 is about 277.3873037505.

Adding to 21343210 its reverse (1234312), we get a palindrome (22577522).

The spelling of 21343210 in words is "twenty-one million, three hundred forty-three thousand, two hundred ten".