21030113123121 has 4 divisors (see below), whose sum is σ = 28040150830832. Its totient is φ = 14020075415412.

The previous prime is 21030113123029. The next prime is 21030113123141. The reversal of 21030113123121 is 12132131103012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21030113123121 - 2³⁹ = 20480357309233 is a prime.

It is a super-2 number, since 2×21030113123121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21030113123141) 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 in 3 ways as a sum of consecutive naturals, for example, 3505018853851 + ... + 3505018853856.

It is an arithmetic number, because the mean of its divisors is an integer number (7010037707708).

Almost surely, 2^{21030113123121} is an apocalyptic number.

It is an amenable number.

21030113123121 is a deficient number, since it is larger than the sum of its proper divisors (7010037707711).

21030113123121 is an equidigital number, since it uses as much as digits as its factorization.

21030113123121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7010037707710.

The product of its (nonzero) digits is 216, while the sum is 21.

Adding to 21030113123121 its reverse (12132131103012), we get a palindrome (33162244226133).

The spelling of 21030113123121 in words is "twenty-one trillion, thirty billion, one hundred thirteen million, one hundred twenty-three thousand, one hundred twenty-one".