20001869 has 4 divisors (see below), whose sum is σ = 20011644. Its totient is φ = 19992096.

The previous prime is 20001853. The next prime is 20001899. The reversal of 20001869 is 96810002.

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 10484644 + 9517225 = 3238^2 + 3085^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001869 - 2⁴ = 20001853 is a prime.

It is a super-2 number, since 2×20001869² = 800149526986322, 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 (20001899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 512 + ... + 6345.

It is an arithmetic number, because the mean of its divisors is an integer number (5002911).

Almost surely, 2^20001869 is an apocalyptic number.

It is an amenable number.

20001869 is a deficient number, since it is larger than the sum of its proper divisors (9775).

20001869 is an equidigital number, since it uses as much as digits as its factorization.

20001869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9774.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 20001869 is about 4472.3449106705. The cubic root of 20001869 is about 271.4502168070.

The spelling of 20001869 in words is "twenty million, one thousand, eight hundred sixty-nine".