21230364 has 12 divisors (see below), whose sum is σ = 49537544. Its totient is φ = 7076784.

The previous prime is 21230359. The next prime is 21230389. The reversal of 21230364 is 46303212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 21230364.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 884587 + ... + 884610.

Almost surely, 2^21230364 is an apocalyptic number.

It is an amenable number.

21230364 is an abundant number, since it is smaller than the sum of its proper divisors (28307180).

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

21230364 is a wasteful number, since it uses less digits than its factorization.

21230364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1769204 (or 1769202 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 21230364 is about 4607.6419131699. The cubic root of 21230364 is about 276.8975714639.

Adding to 21230364 its reverse (46303212), we get a palindrome (67533576).

The spelling of 21230364 in words is "twenty-one million, two hundred thirty thousand, three hundred sixty-four".