20716387 has 12 divisors (see below), whose sum is σ = 22263640. Its totient is φ = 19270656.

The previous prime is 20716379. The next prime is 20716391. The reversal of 20716387 is 78361702.

It is not a de Polignac number, because 20716387 - 2³ = 20716379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20716187) 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 11 ways as a sum of consecutive naturals, for example, 27664 + ... + 28402.

Almost surely, 2^20716387 is an apocalyptic number.

20716387 is a deficient number, since it is larger than the sum of its proper divisors (1547253).

20716387 is an equidigital number, since it uses as much as digits as its factorization.

20716387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 870 (or 853 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 20716387 is about 4551.5257881286. The cubic root of 20716387 is about 274.6447732953.

The spelling of 20716387 in words is "twenty million, seven hundred sixteen thousand, three hundred eighty-seven".