21124231001 has 2 divisors, whose sum is σ = 21124231002. Its totient is φ = 21124231000.

The previous prime is 21124230997. The next prime is 21124231019. The reversal of 21124231001 is 10013242112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20695699600 + 428531401 = 143860^2 + 20701^2 .

It is a cyclic number.

It is not a de Polignac number, because 21124231001 - 2² = 21124230997 is a prime.

It is not a weakly prime, because it can be changed into another prime (21124231091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562115500 + 10562115501.

It is an arithmetic number, because the mean of its divisors is an integer number (10562115501).

Almost surely, 2^21124231001 is an apocalyptic number.

It is an amenable number.

21124231001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124231001 is an equidigital number, since it uses as much as digits as its factorization.

21124231001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21124231001 its reverse (10013242112), we get a palindrome (31137473113).

The spelling of 21124231001 in words is "twenty-one billion, one hundred twenty-four million, two hundred thirty-one thousand, one".