21111210031 has 8 divisors (see below), whose sum is σ = 22031301600. Its totient is φ = 20191302912.

The previous prime is 21111210019. The next prime is 21111210037. The reversal of 21111210031 is 13001211112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21111210031 - 2¹¹ = 21111207983 is a prime.

It is a super-2 number, since 2×21111210031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21111209993 and 21111210020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111210037) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220695 + ... + 301543.

It is an arithmetic number, because the mean of its divisors is an integer number (2753912700).

Almost surely, 2^21111210031 is an apocalyptic number.

21111210031 is a deficient number, since it is larger than the sum of its proper divisors (920091569).

21111210031 is a wasteful number, since it uses less digits than its factorization.

21111210031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92225.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21111210031 its reverse (13001211112), we get a palindrome (34112421143).

The spelling of 21111210031 in words is "twenty-one billion, one hundred eleven million, two hundred ten thousand, thirty-one".