20221687 has 8 divisors (see below), whose sum is σ = 21633696. Its totient is φ = 18834432.

The previous prime is 20221679. The next prime is 20221693. The reversal of 20221687 is 78612202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20221687 - 2³ = 20221679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20221697) 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, 4483 + ... + 7780.

It is an arithmetic number, because the mean of its divisors is an integer number (2704212).

Almost surely, 2^20221687 is an apocalyptic number.

20221687 is a deficient number, since it is larger than the sum of its proper divisors (1412009).

20221687 is a wasteful number, since it uses less digits than its factorization.

20221687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12377.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 20221687 is about 4496.8530107176. The cubic root of 20221687 is about 272.4409972414.

Adding to 20221687 its reverse (78612202), we get a palindrome (98833889).

The spelling of 20221687 in words is "twenty million, two hundred twenty-one thousand, six hundred eighty-seven".