20100104 has 8 divisors (see below), whose sum is σ = 37687710. Its totient is φ = 10050048.

The previous prime is 20100097. The next prime is 20100149. The reversal of 20100104 is 40100102.

It can be written as a sum of positive squares in only one way, i.e., 19377604 + 722500 = 4402^2 + 850^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a Harshad number since it is a multiple of its sum of digits (8), and also a Moran number because the ratio is a prime number: 2512513 = 20100104 / (2 + 0 + 1 + 0 + 0 + 1 + 0 + 4).

It is a junction number, because it is equal to n+sod(n) for n = 20100091 and 20100100.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1256249 + ... + 1256264.

Almost surely, 2^20100104 is an apocalyptic number.

It is an amenable number.

20100104 is a deficient number, since it is larger than the sum of its proper divisors (17587606).

20100104 is a wasteful number, since it uses less digits than its factorization.

20100104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2512519 (or 2512515 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 20100104 is about 4483.3139528701. The cubic root of 20100104 is about 271.8938816146.

Adding to 20100104 its reverse (40100102), we get a palindrome (60200206).

The spelling of 20100104 in words is "twenty million, one hundred thousand, one hundred four".