21310463 has 4 divisors (see below), whose sum is σ = 21351888. Its totient is φ = 21269040.

The previous prime is 21310459. The next prime is 21310477. The reversal of 21310463 is 36401312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21310463 - 2² = 21310459 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21310433) 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, 19931 + ... + 20972.

It is an arithmetic number, because the mean of its divisors is an integer number (5337972).

Almost surely, 2^21310463 is an apocalyptic number.

21310463 is a deficient number, since it is larger than the sum of its proper divisors (41425).

21310463 is an equidigital number, since it uses as much as digits as its factorization.

21310463 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41424.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 21310463 is about 4616.3257034139. The cubic root of 21310463 is about 277.2453655311.

Adding to 21310463 its reverse (36401312), we get a palindrome (57711775).

The spelling of 21310463 in words is "twenty-one million, three hundred ten thousand, four hundred sixty-three".