20981712 has 40 divisors (see below), whose sum is σ = 54371520. Its totient is φ = 6972160.

The previous prime is 20981711. The next prime is 20981747. The reversal of 20981712 is 21718902.

It is a self number, because there is not a number n which added to its sum of digits gives 20981712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20981711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24589 + ... + 25427.

It is an arithmetic number, because the mean of its divisors is an integer number (1359288).

Almost surely, 2^20981712 is an apocalyptic number.

It is an amenable number.

20981712 is an abundant number, since it is smaller than the sum of its proper divisors (33389808).

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

20981712 is a wasteful number, since it uses less digits than its factorization.

20981712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1371 (or 1365 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 20981712 is about 4580.5798759546. The cubic root of 20981712 is about 275.8123067510.

The spelling of 20981712 in words is "twenty million, nine hundred eighty-one thousand, seven hundred twelve".