21123310013 has 16 divisors (see below), whose sum is σ = 23033625216. Its totient is φ = 19254006720.

The previous prime is 21123309997. The next prime is 21123310037. The reversal of 21123310013 is 31001332112.

It is not a de Polignac number, because 21123310013 - 2⁴ = 21123309997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21123309973 and 21123310000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123310073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3111683 + ... + 3118463.

It is an arithmetic number, because the mean of its divisors is an integer number (1439601576).

Almost surely, 2^21123310013 is an apocalyptic number.

It is an amenable number.

21123310013 is a deficient number, since it is larger than the sum of its proper divisors (1910315203).

21123310013 is a wasteful number, since it uses less digits than its factorization.

21123310013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9764.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21123310013 its reverse (31001332112), we get a palindrome (52124642125).

The spelling of 21123310013 in words is "twenty-one billion, one hundred twenty-three million, three hundred ten thousand, thirteen".