21040363 has 4 divisors (see below), whose sum is σ = 21050928. Its totient is φ = 21029800.

The previous prime is 21040297. The next prime is 21040387. The reversal of 21040363 is 36304012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21040363 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21040363.

It is not an unprimeable number, because it can be changed into a prime (21040463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1288 + ... + 6613.

It is an arithmetic number, because the mean of its divisors is an integer number (5262732).

Almost surely, 2^21040363 is an apocalyptic number.

21040363 is a deficient number, since it is larger than the sum of its proper divisors (10565).

21040363 is an equidigital number, since it uses as much as digits as its factorization.

21040363 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10564.

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 21040363 is about 4586.9775451816. The cubic root of 21040363 is about 276.0690639670.

Adding to 21040363 its reverse (36304012), we get a palindrome (57344375).

The spelling of 21040363 in words is "twenty-one million, forty thousand, three hundred sixty-three".