21103310 has 16 divisors (see below), whose sum is σ = 38125296. Its totient is φ = 8410368.

The previous prime is 21103309. The next prime is 21103321. The reversal of 21103310 is 1330112.

It is a super-2 number, since 2×21103310² = 890699385912200, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21103291 and 21103300.

It is a congruent number.

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, 899 + ... + 6558.

It is an arithmetic number, because the mean of its divisors is an integer number (2382831).

Almost surely, 2^21103310 is an apocalyptic number.

21103310 is a deficient number, since it is larger than the sum of its proper divisors (17021986).

21103310 is a wasteful number, since it uses less digits than its factorization.

21103310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7747.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21103310 is about 4593.8339107983. The cubic root of 21103310 is about 276.3440975350.

Adding to 21103310 its reverse (1330112), we get a palindrome (22433422).

The spelling of 21103310 in words is "twenty-one million, one hundred three thousand, three hundred ten".