20912 has 10 divisors (see below), whose sum is σ = 40548. Its totient is φ = 10448.

The previous prime is 20903. The next prime is 20921. The reversal of 20912 is 21902.

20912 is an esthetic number in base 14, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (20903) and next prime (20921).

It is an Ulam number.

It is a plaindrome in base 14.

It is an unprimeable number.

20912 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 as a sum of consecutive naturals, namely, 638 + ... + 669.

2²⁰⁹¹² is an apocalyptic number.

It is an amenable number.

20912 is a deficient number, since it is larger than the sum of its proper divisors (19636).

20912 is a wasteful number, since it uses less digits than its factorization.

20912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1315 (or 1309 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 20912 is about 144.6098198602. The cubic root of 20912 is about 27.5506504546.

Subtracting 20912 from its reverse (21902), we obtain a triangular number (990 = T₄₄).

The spelling of 20912 in words is "twenty thousand, nine hundred twelve".