21366463 has 2 divisors, whose sum is σ = 21366464. Its totient is φ = 21366462.

The previous prime is 21366407. The next prime is 21366487. The reversal of 21366463 is 36466312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21366463 is a prime.

It is a super-2 number, since 2×21366463² = 913051482260738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21366403) 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 as a sum of consecutive naturals, namely, 10683231 + 10683232.

It is an arithmetic number, because the mean of its divisors is an integer number (10683232).

Almost surely, 2^21366463 is an apocalyptic number.

21366463 is a deficient number, since it is larger than the sum of its proper divisors (1).

21366463 is an equidigital number, since it uses as much as digits as its factorization.

21366463 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 31.

The square root of 21366463 is about 4622.3871538416. The cubic root of 21366463 is about 277.4880031607.

The spelling of 21366463 in words is "twenty-one million, three hundred sixty-six thousand, four hundred sixty-three".