20975646 has 8 divisors (see below), whose sum is σ = 41951304. Its totient is φ = 6991880.

The previous prime is 20975627. The next prime is 20975657. The reversal of 20975646 is 64657902.

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

20975646 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1747965 + ... + 1747976.

It is an arithmetic number, because the mean of its divisors is an integer number (5243913).

Almost surely, 2^20975646 is an apocalyptic number.

20975646 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20975646 is a wasteful number, since it uses less digits than its factorization.

20975646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3495946.

The product of its (nonzero) digits is 90720, while the sum is 39.

The square root of 20975646 is about 4579.9176848498. The cubic root of 20975646 is about 275.7857242568.

It can be divided in two parts, 209 and 75646, that added together give a triangular number (75855 = T₃₈₉).

The spelling of 20975646 in words is "twenty million, nine hundred seventy-five thousand, six hundred forty-six".