20010123 has 12 divisors (see below), whose sum is σ = 33032688. Its totient is φ = 11434320.

The previous prime is 20010079. The next prime is 20010127. The reversal of 20010123 is 32101002.

It is a happy number.

It is not a de Polignac number, because 20010123 - 2⁹ = 20009611 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (20010127) 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 11 ways as a sum of consecutive naturals, for example, 158748 + ... + 158873.

It is an arithmetic number, because the mean of its divisors is an integer number (2752724).

Almost surely, 2^20010123 is an apocalyptic number.

20010123 is a deficient number, since it is larger than the sum of its proper divisors (13022565).

20010123 is a wasteful number, since it uses less digits than its factorization.

20010123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317634 (or 317631 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 20010123 is about 4473.2675976293. The cubic root of 20010123 is about 271.4875506842.

Adding to 20010123 its reverse (32101002), we get a palindrome (52111125).

The spelling of 20010123 in words is "twenty million, ten thousand, one hundred twenty-three".