21230310 has 16 divisors (see below), whose sum is σ = 50952816. Its totient is φ = 5661408.

The previous prime is 21230309. The next prime is 21230329. The reversal of 21230310 is 1303212.

It is a happy number.

It is a super-2 number, since 2×21230310² = 901452125392200, which contains 22 as substring.

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, 353809 + ... + 353868.

It is an arithmetic number, because the mean of its divisors is an integer number (3184551).

Almost surely, 2^21230310 is an apocalyptic number.

21230310 is an abundant number, since it is smaller than the sum of its proper divisors (29722506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21230310 is a wasteful number, since it uses less digits than its factorization.

21230310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 707687.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21230310 is about 4607.6360533358. The cubic root of 21230310 is about 276.8973366982.

Adding to 21230310 its reverse (1303212), we get a palindrome (22533522).

The spelling of 21230310 in words is "twenty-one million, two hundred thirty thousand, three hundred ten".