20681916 has 24 divisors (see below), whose sum is σ = 48370560. Its totient is φ = 6877872.

The previous prime is 20681893. The next prime is 20681933. The reversal of 20681916 is 61918602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4075 + ... + 7613.

It is an arithmetic number, because the mean of its divisors is an integer number (2015440).

Almost surely, 2^20681916 is an apocalyptic number.

It is an amenable number.

20681916 is an abundant number, since it is smaller than the sum of its proper divisors (27688644).

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

20681916 is a wasteful number, since it uses less digits than its factorization.

20681916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4033 (or 4031 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 20681916 is about 4547.7374594407. The cubic root of 20681916 is about 274.4923571450.

The spelling of 20681916 in words is "twenty million, six hundred eighty-one thousand, nine hundred sixteen".