21310456 has 16 divisors (see below), whose sum is σ = 40887000. Its totient is φ = 10407264.

The previous prime is 21310453. The next prime is 21310459. The reversal of 21310456 is 65401312.

It is an interprime number because it is at equal distance from previous prime (21310453) and next prime (21310459).

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21310451) by changing a digit.

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, 30631 + ... + 31318.

Almost surely, 2^21310456 is an apocalyptic number.

It is an amenable number.

21310456 is a deficient number, since it is larger than the sum of its proper divisors (19576544).

21310456 is a wasteful number, since it uses less digits than its factorization.

21310456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61998 (or 61994 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21310456 is about 4616.3249452351. The cubic root of 21310456 is about 277.2453351748.

Adding to 21310456 its reverse (65401312), we get a palindrome (86711768).

The spelling of 21310456 in words is "twenty-one million, three hundred ten thousand, four hundred fifty-six".