21111232013 has 4 divisors (see below), whose sum is σ = 21263111520. Its totient is φ = 20959352508.

The previous prime is 21111231997. The next prime is 21111232057. The reversal of 21111232013 is 31023211112.

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 a cyclic number.

It is not a de Polignac number, because 21111232013 - 2⁴ = 21111231997 is a prime.

It is a super-3 number, since 3×21111232013³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21111231982 and 21111232000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111231013) 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, 75939545 + ... + 75939822.

It is an arithmetic number, because the mean of its divisors is an integer number (5315777880).

Almost surely, 2^21111232013 is an apocalyptic number.

It is an amenable number.

21111232013 is a deficient number, since it is larger than the sum of its proper divisors (151879507).

21111232013 is a wasteful number, since it uses less digits than its factorization.

21111232013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151879506.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21111232013 its reverse (31023211112), we get a palindrome (52134443125).

The spelling of 21111232013 in words is "twenty-one billion, one hundred eleven million, two hundred thirty-two thousand, thirteen".