10123030021 has 4 divisors (see below), whose sum is σ = 10901724652. Its totient is φ = 9344335392.

The previous prime is 10123030013. The next prime is 10123030091. The reversal of 10123030021 is 12003032101.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2638876900 + 7484153121 = 51370^2 + 86511^2 .

It is a cyclic number.

It is not a de Polignac number, because 10123030021 - 2³ = 10123030013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 778694617 = 10123030021 / (1 + 0 + 1 + 2 + 3 + 0 + 3 + 0 + 0 + 2 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 10123029983 and 10123030010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10123030091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 389347296 + ... + 389347321.

It is an arithmetic number, because the mean of its divisors is an integer number (2725431163).

Almost surely, 2^10123030021 is an apocalyptic number.

It is an amenable number.

10123030021 is a deficient number, since it is larger than the sum of its proper divisors (778694631).

10123030021 is an equidigital number, since it uses as much as digits as its factorization.

10123030021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778694630.

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

Adding to 10123030021 its reverse (12003032101), we get a palindrome (22126062122).

The spelling of 10123030021 in words is "ten billion, one hundred twenty-three million, thirty thousand, twenty-one".