20102789 has 12 divisors (see below), whose sum is σ = 24761484. Its totient is φ = 16216704.

The previous prime is 20102743. The next prime is 20102807. The reversal of 20102789 is 98720102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12496225 + 7606564 = 3535^2 + 2758^2 .

It is not a de Polignac number, because 20102789 - 2¹² = 20098693 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20102389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11234 + ... + 12899.

It is an arithmetic number, because the mean of its divisors is an integer number (2063457).

Almost surely, 2^20102789 is an apocalyptic number.

It is an amenable number.

20102789 is a deficient number, since it is larger than the sum of its proper divisors (4658695).

20102789 is a wasteful number, since it uses less digits than its factorization.

20102789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24164 (or 24157 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 20102789 is about 4483.6133865444. The cubic root of 20102789 is about 271.9059877306.

The spelling of 20102789 in words is "twenty million, one hundred two thousand, seven hundred eighty-nine".