20388169 has 4 divisors (see below), whose sum is σ = 20460496. Its totient is φ = 20315844.

The previous prime is 20388161. The next prime is 20388191. The reversal of 20388169 is 96188302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20388169 - 2³ = 20388161 is a prime.

It is a super-2 number, since 2×20388169² = 831354870345122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20388161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35739 + ... + 36304.

It is an arithmetic number, because the mean of its divisors is an integer number (5115124).

Almost surely, 2^20388169 is an apocalyptic number.

It is an amenable number.

20388169 is a deficient number, since it is larger than the sum of its proper divisors (72327).

20388169 is an equidigital number, since it uses as much as digits as its factorization.

20388169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72326.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 20388169 is about 4515.3260125931. The cubic root of 20388169 is about 273.1866095675.

The spelling of 20388169 in words is "twenty million, three hundred eighty-eight thousand, one hundred sixty-nine".