20999463 has 4 divisors (see below), whose sum is σ = 27999288. Its totient is φ = 13999640.

The previous prime is 20999443. The next prime is 20999467. The reversal of 20999463 is 36499902.

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 20999463 - 2⁹ = 20998951 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20999467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3499908 + ... + 3499913.

It is an arithmetic number, because the mean of its divisors is an integer number (6999822).

Almost surely, 2^20999463 is an apocalyptic number.

20999463 is a deficient number, since it is larger than the sum of its proper divisors (6999825).

20999463 is an equidigital number, since it uses as much as digits as its factorization.

20999463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6999824.

The product of its (nonzero) digits is 104976, while the sum is 42.

The square root of 20999463 is about 4582.5171030777. The cubic root of 20999463 is about 275.8900659636.

The spelling of 20999463 in words is "twenty million, nine hundred ninety-nine thousand, four hundred sixty-three".