21010030123 has 2 divisors, whose sum is σ = 21010030124. Its totient is φ = 21010030122.

The previous prime is 21010030109. The next prime is 21010030127. The reversal of 21010030123 is 32103001012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21010030123 - 2²⁵ = 20976475691 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010030127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505015061 + 10505015062.

It is an arithmetic number, because the mean of its divisors is an integer number (10505015062).

Almost surely, 2^21010030123 is an apocalyptic number.

21010030123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010030123 is an equidigital number, since it uses as much as digits as its factorization.

21010030123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21010030123 its reverse (32103001012), we get a palindrome (53113031135).

The spelling of 21010030123 in words is "twenty-one billion, ten million, thirty thousand, one hundred twenty-three".