21440463 has 16 divisors (see below), whose sum is σ = 31700352. Its totient is φ = 12780000.

The previous prime is 21440453. The next prime is 21440473. The reversal of 21440463 is 36404412.

It is an interprime number because it is at equal distance from previous prime (21440453) and next prime (21440473).

It is not a de Polignac number, because 21440463 - 2⁵ = 21440431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440453) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3313 + ... + 7338.

It is an arithmetic number, because the mean of its divisors is an integer number (1981272).

Almost surely, 2^21440463 is an apocalyptic number.

21440463 is a deficient number, since it is larger than the sum of its proper divisors (10259889).

21440463 is a wasteful number, since it uses less digits than its factorization.

21440463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10726.

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 21440463 is about 4630.3847572313. The cubic root of 21440463 is about 277.8079820608.

Adding to 21440463 its reverse (36404412), we get a palindrome (57844875).

The spelling of 21440463 in words is "twenty-one million, four hundred forty thousand, four hundred sixty-three".