21430210 has 16 divisors (see below), whose sum is σ = 38973816. Its totient is φ = 8483328.

The previous prime is 21430193. The next prime is 21430229. The reversal of 21430210 is 1203412.

It can be written as a sum of positive squares in 4 ways, for example, as 20169081 + 1261129 = 4491^2 + 1123^2 .

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, 10077 + ... + 12016.

Almost surely, 2^21430210 is an apocalyptic number.

21430210 is a deficient number, since it is larger than the sum of its proper divisors (17543606).

21430210 is a wasteful number, since it uses less digits than its factorization.

21430210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22197.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21430210 is about 4629.2774814219. The cubic root of 21430210 is about 277.7636916709.

Adding to 21430210 its reverse (1203412), we get a palindrome (22633622).

The spelling of 21430210 in words is "twenty-one million, four hundred thirty thousand, two hundred ten".