21363442 has 8 divisors (see below), whose sum is σ = 32165100. Its totient is φ = 10641744.

The previous prime is 21363439. The next prime is 21363443. The reversal of 21363442 is 24436312.

It can be written as a sum of positive squares in 2 ways, for example, as 21353641 + 9801 = 4621^2 + 99^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21363443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19317 + ... + 20392.

Almost surely, 2^21363442 is an apocalyptic number.

21363442 is a deficient number, since it is larger than the sum of its proper divisors (10801658).

21363442 is a wasteful number, since it uses less digits than its factorization.

21363442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39980.

The product of its digits is 3456, while the sum is 25.

The square root of 21363442 is about 4622.0603630848. The cubic root of 21363442 is about 277.4749245529.

Adding to 21363442 its reverse (24436312), we get a palindrome (45799754).

The spelling of 21363442 in words is "twenty-one million, three hundred sixty-three thousand, four hundred forty-two".