20712 has 16 divisors (see below), whose sum is σ = 51840. Its totient is φ = 6896.

The previous prime is 20707. The next prime is 20717. The reversal of 20712 is 21702.

It is an interprime number because it is at equal distance from previous prime (20707) and next prime (20717).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (20717) by changing a digit.

20712 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 408 + ... + 455.

It is an arithmetic number, because the mean of its divisors is an integer number (3240).

2²⁰⁷¹² is an apocalyptic number.

It is an amenable number.

20712 is an abundant number, since it is smaller than the sum of its proper divisors (31128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25920).

20712 is a wasteful number, since it uses less digits than its factorization.

20712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 872 (or 868 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 12.

The square root of 20712 is about 143.9166425400. The cubic root of 20712 is about 27.4625385235.

Subtracting 20712 from its reverse (21702), we obtain a triangular number (990 = T₄₄).

The spelling of 20712 in words is "twenty thousand, seven hundred twelve", and thus it is an iban number.