21266463 has 4 divisors (see below), whose sum is σ = 28355288. Its totient is φ = 14177640.

The previous prime is 21266449. The next prime is 21266471. The reversal of 21266463 is 36466212.

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

It is not a de Polignac number, because 21266463 - 2⁸ = 21266207 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 21266463.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21261463) 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, 3544408 + ... + 3544413.

It is an arithmetic number, because the mean of its divisors is an integer number (7088822).

Almost surely, 2^21266463 is an apocalyptic number.

21266463 is a deficient number, since it is larger than the sum of its proper divisors (7088825).

21266463 is an equidigital number, since it uses as much as digits as its factorization.

21266463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7088824.

The product of its digits is 10368, while the sum is 30.

The square root of 21266463 is about 4611.5575459925. The cubic root of 21266463 is about 277.0544233102.

The spelling of 21266463 in words is "twenty-one million, two hundred sixty-six thousand, four hundred sixty-three".