20901686 has 8 divisors (see below), whose sum is σ = 33764304. Its totient is φ = 9646920.

The previous prime is 20901667. The next prime is 20901697. The reversal of 20901686 is 68610902.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 401930 + ... + 401981.

It is an arithmetic number, because the mean of its divisors is an integer number (4220538).

Almost surely, 2^20901686 is an apocalyptic number.

20901686 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20901686 is a deficient number, since it is larger than the sum of its proper divisors (12862618).

20901686 is a wasteful number, since it uses less digits than its factorization.

20901686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 803926.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 20901686 is about 4571.8361737928. The cubic root of 20901686 is about 275.4612029429.

The spelling of 20901686 in words is "twenty million, nine hundred one thousand, six hundred eighty-six".