20101010 has 16 divisors (see below), whose sum is σ = 36248472. Its totient is φ = 8025600.

The previous prime is 20101009. The next prime is 20101013. The reversal of 20101010 is 1010102.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 20097289 + 3721 = 4483^2 + 61^2 .

It is a Harshad number since it is a multiple of its sum of digits (5).

20101010 is a modest number, since divided by 101010 gives 20 as remainder.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20100985 and 20101003.

It is not an unprimeable number, because it can be changed into a prime (20101013) 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 7 ways as a sum of consecutive naturals, for example, 5090 + ... + 8130.

Almost surely, 2^20101010 is an apocalyptic number.

20101010 is a deficient number, since it is larger than the sum of its proper divisors (16147462).

20101010 is a wasteful number, since it uses less digits than its factorization.

20101010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3709.

The product of its (nonzero) digits is 2, while the sum is 5.

The square root of 20101010 is about 4483.4149930605. The cubic root of 20101010 is about 271.8979667039.

Adding to 20101010 its reverse (1010102), we get a palindrome (21111112).

The spelling of 20101010 in words is "twenty million, one hundred one thousand, ten".