20021100123 has 8 divisors (see below), whose sum is σ = 26705105488. Its totient is φ = 13342247424.

The previous prime is 20021100119. The next prime is 20021100137. The reversal of 20021100123 is 32100112002.

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

It is not a de Polignac number, because 20021100123 - 2² = 20021100119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20021100099 and 20021100108.

It is not an unprimeable number, because it can be changed into a prime (20021100163) 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, 1279090 + ... + 1294647.

It is an arithmetic number, because the mean of its divisors is an integer number (3338138186).

Almost surely, 2^20021100123 is an apocalyptic number.

20021100123 is a deficient number, since it is larger than the sum of its proper divisors (6684005365).

20021100123 is a wasteful number, since it uses less digits than its factorization.

20021100123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2576333.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 20021100123 its reverse (32100112002), we get a palindrome (52121212125).

The spelling of 20021100123 in words is "twenty billion, twenty-one million, one hundred thousand, one hundred twenty-three".