20102005 has 24 divisors (see below), whose sum is σ = 30615840. Its totient is φ = 12529440.

The previous prime is 20102003. The next prime is 20102009. The reversal of 20102005 is 50020102.

It is not a de Polignac number, because 20102005 - 2¹ = 20102003 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20101982 and 20102000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20102003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1035 + ... + 6424.

It is an arithmetic number, because the mean of its divisors is an integer number (1275660).

Almost surely, 2^20102005 is an apocalyptic number.

It is an amenable number.

20102005 is a deficient number, since it is larger than the sum of its proper divisors (10513835).

20102005 is a wasteful number, since it uses less digits than its factorization.

20102005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7489 (or 7482 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 10.

The square root of 20102005 is about 4483.5259562090. The cubic root of 20102005 is about 271.9024529463.

Adding to 20102005 its reverse (50020102), we get a palindrome (70122107).

The spelling of 20102005 in words is "twenty million, one hundred two thousand, five".