21012011120123 has 8 divisors (see below), whose sum is σ = 21496099887360. Its totient is φ = 20532187452520.

The previous prime is 21012011120069. The next prime is 21012011120129. The reversal of 21012011120123 is 32102111021012.

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 21012011120123 - 2²⁴ = 21011994342907 is a prime.

It is a super-2 number, since 2×21012011120123² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012011120129) 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, 1066264943 + ... + 1066284648.

It is an arithmetic number, because the mean of its divisors is an integer number (2687012485920).

Almost surely, 2^{21012011120123} is an apocalyptic number.

21012011120123 is a deficient number, since it is larger than the sum of its proper divisors (484088767237).

21012011120123 is a wasteful number, since it uses less digits than its factorization.

21012011120123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2132549817.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 21012011120123 its reverse (32102111021012), we get a palindrome (53114122141135).

The spelling of 21012011120123 in words is "twenty-one trillion, twelve billion, eleven million, one hundred twenty thousand, one hundred twenty-three".