21123554334 has 16 divisors (see below), whose sum is σ = 42825837072. Its totient is φ = 6944730048.

The previous prime is 21123554321. The next prime is 21123554339. The reversal of 21123554334 is 43345532112.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21123554295 and 21123554304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123554339) 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, 24113209 + ... + 24114084.

It is an arithmetic number, because the mean of its divisors is an integer number (2676614817).

Almost surely, 2^21123554334 is an apocalyptic number.

21123554334 is an abundant number, since it is smaller than the sum of its proper divisors (21702282738).

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

21123554334 is a wasteful number, since it uses less digits than its factorization.

21123554334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48227371.

The product of its digits is 43200, while the sum is 33.

The spelling of 21123554334 in words is "twenty-one billion, one hundred twenty-three million, five hundred fifty-four thousand, three hundred thirty-four".