21123200001 has 16 divisors (see below), whose sum is σ = 28650928320. Its totient is φ = 13838957760.

The previous prime is 21123199997. The next prime is 21123200027. The reversal of 21123200001 is 10000232112.

It is not a de Polignac number, because 21123200001 - 2² = 21123199997 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21123200001.

It is not an unprimeable number, because it can be changed into a prime (21123205001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 579331 + ... + 614711.

It is an arithmetic number, because the mean of its divisors is an integer number (1790683020).

Almost surely, 2^21123200001 is an apocalyptic number.

It is an amenable number.

21123200001 is a deficient number, since it is larger than the sum of its proper divisors (7527728319).

21123200001 is a wasteful number, since it uses less digits than its factorization.

21123200001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38816.

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

Adding to 21123200001 its reverse (10000232112), we get a palindrome (31123432113).

The spelling of 21123200001 in words is "twenty-one billion, one hundred twenty-three million, two hundred thousand, one".