20987463 has 16 divisors (see below), whose sum is σ = 32368896. Its totient is φ = 11847360.

The previous prime is 20987453. The next prime is 20987479. The reversal of 20987463 is 36478902.

It is not a de Polignac number, because 20987463 - 2¹⁰ = 20986439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20987413) 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 15 ways as a sum of consecutive naturals, for example, 4278 + ... + 7763.

It is an arithmetic number, because the mean of its divisors is an integer number (2023056).

Almost surely, 2^20987463 is an apocalyptic number.

20987463 is a deficient number, since it is larger than the sum of its proper divisors (11381433).

20987463 is a wasteful number, since it uses less digits than its factorization.

20987463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12134.

The product of its (nonzero) digits is 72576, while the sum is 39.

The square root of 20987463 is about 4581.2075918910. The cubic root of 20987463 is about 275.8375041178.

The spelling of 20987463 in words is "twenty million, nine hundred eighty-seven thousand, four hundred sixty-three".