20671688 has 16 divisors (see below), whose sum is σ = 39137280. Its totient is φ = 10235088.

The previous prime is 20671661. The next prime is 20671723. The reversal of 20671688 is 88617602.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 11720 + ... + 13367.

It is an arithmetic number, because the mean of its divisors is an integer number (2446080).

Almost surely, 2^20671688 is an apocalyptic number.

It is an amenable number.

20671688 is a deficient number, since it is larger than the sum of its proper divisors (18465592).

20671688 is a wasteful number, since it uses less digits than its factorization.

20671688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25196 (or 25192 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 20671688 is about 4546.6128051551. The cubic root of 20671688 is about 274.4471006874.

The spelling of 20671688 in words is "twenty million, six hundred seventy-one thousand, six hundred eighty-eight".