20864169 has 16 divisors (see below), whose sum is σ = 30995200. Its totient is φ = 13871088.

The previous prime is 20864161. The next prime is 20864171. The reversal of 20864169 is 96146802.

20864169 is a `hidden beast` number, since 2 + 0 + 8 + 641 + 6 + 9 = 666.

It is not a de Polignac number, because 20864169 - 2³ = 20864161 is a prime.

It is a super-2 number, since 2×20864169² = 870627096121122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20864161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11667 + ... + 13335.

It is an arithmetic number, because the mean of its divisors is an integer number (1937200).

Almost surely, 2^20864169 is an apocalyptic number.

It is an amenable number.

20864169 is a deficient number, since it is larger than the sum of its proper divisors (10131031).

20864169 is a wasteful number, since it uses less digits than its factorization.

20864169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2141 (or 2135 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 20864169 is about 4567.7312749329. The cubic root of 20864169 is about 275.2962933221.

The spelling of 20864169 in words is "twenty million, eight hundred sixty-four thousand, one hundred sixty-nine".