20166869 has 4 divisors (see below), whose sum is σ = 20178444. Its totient is φ = 20155296.

The previous prime is 20166851. The next prime is 20166877. The reversal of 20166869 is 96866102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 5244100 + 14922769 = 2290^2 + 3863^2 .

It is a cyclic number.

It is not a de Polignac number, because 20166869 - 2¹² = 20162773 is a prime.

It is a super-2 number, since 2×20166869² = 813405210526322, 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 (20166829) 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, 2582 + ... + 6855.

It is an arithmetic number, because the mean of its divisors is an integer number (5044611).

Almost surely, 2^20166869 is an apocalyptic number.

It is an amenable number.

20166869 is a deficient number, since it is larger than the sum of its proper divisors (11575).

20166869 is an equidigital number, since it uses as much as digits as its factorization.

20166869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11574.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 20166869 is about 4490.7537229289. The cubic root of 20166869 is about 272.1945920466.

The spelling of 20166869 in words is "twenty million, one hundred sixty-six thousand, eight hundred sixty-nine".