20121123210 has 32 divisors (see below), whose sum is σ = 48412363392. Its totient is φ = 5352114240.

The previous prime is 20121123203. The next prime is 20121123227. The reversal of 20121123210 is 1232112102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20121123210.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 832806 + ... + 856625.

It is an arithmetic number, because the mean of its divisors is an integer number (1512886356).

Almost surely, 2^20121123210 is an apocalyptic number.

20121123210 is an abundant number, since it is smaller than the sum of its proper divisors (28291240182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20121123210 is a wasteful number, since it uses less digits than its factorization.

20121123210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1689838.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 20121123210 its reverse (1232112102), we get a palindrome (21353235312).

The spelling of 20121123210 in words is "twenty billion, one hundred twenty-one million, one hundred twenty-three thousand, two hundred ten".