20211220123 has 8 divisors (see below), whose sum is σ = 21092020128. Its totient is φ = 19330591104.

The previous prime is 20211220063. The next prime is 20211220147. The reversal of 20211220123 is 32102211202.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20211220123 - 2¹³ = 20211211931 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20211220097 and 20211220106.

It is not an unprimeable number, because it can be changed into a prime (20211220153) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238161 + ... + 311677.

It is an arithmetic number, because the mean of its divisors is an integer number (2636502516).

Almost surely, 2^20211220123 is an apocalyptic number.

20211220123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20211220123 is a deficient number, since it is larger than the sum of its proper divisors (880800005).

20211220123 is a wasteful number, since it uses less digits than its factorization.

20211220123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85493.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20211220123 its reverse (32102211202), we get a palindrome (52313431325).

The spelling of 20211220123 in words is "twenty billion, two hundred eleven million, two hundred twenty thousand, one hundred twenty-three".