21103331123 has 18 divisors (see below), whose sum is σ = 26077779756. Its totient is φ = 17024524608.

The previous prime is 21103331111. The next prime is 21103331143. The reversal of 21103331123 is 32113330112.

It is not a de Polignac number, because 21103331123 - 2¹⁶ = 21103265587 is a prime.

It is a super-2 number, since 2×21103331123² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21103331095 and 21103331104.

It is not an unprimeable number, because it can be changed into a prime (21103331143) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 730961 + ... + 759282.

It is an arithmetic number, because the mean of its divisors is an integer number (1448765542).

Almost surely, 2^21103331123 is an apocalyptic number.

21103331123 is a deficient number, since it is larger than the sum of its proper divisors (4974448633).

21103331123 is a wasteful number, since it uses less digits than its factorization.

21103331123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1490291 (or 1490267 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 21103331123 its reverse (32113330112), we get a palindrome (53216661235).

The spelling of 21103331123 in words is "twenty-one billion, one hundred three million, three hundred thirty-one thousand, one hundred twenty-three".