21000001100123 has 8 divisors (see below), whose sum is σ = 21068375286816. Its totient is φ = 20931632363200.

The previous prime is 21000001100077. The next prime is 21000001100161. The reversal of 21000001100123 is 32100110000012.

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 21000001100123 - 2⁸ = 21000001099867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000001120123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6429263 + ... + 9128823.

It is an arithmetic number, because the mean of its divisors is an integer number (2633546910852).

Almost surely, 2^{21000001100123} is an apocalyptic number.

21000001100123 is a deficient number, since it is larger than the sum of its proper divisors (68374186693).

21000001100123 is a wasteful number, since it uses less digits than its factorization.

21000001100123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2724885.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21000001100123 its reverse (32100110000012), we get a palindrome (53100111100135).

The spelling of 21000001100123 in words is "twenty-one trillion, one million, one hundred thousand, one hundred twenty-three".