21110021231 has 8 divisors (see below), whose sum is σ = 23930388720. Its totient is φ = 18460585152.

The previous prime is 21110021221. The next prime is 21110021239. The reversal of 21110021231 is 13212001112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21110021231 is a prime.

It is a super-2 number, since 2×21110021231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110021239) 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, 42732590 + ... + 42733083.

It is an arithmetic number, because the mean of its divisors is an integer number (2991298590).

Almost surely, 2^21110021231 is an apocalyptic number.

21110021231 is a deficient number, since it is larger than the sum of its proper divisors (2820367489).

21110021231 is a wasteful number, since it uses less digits than its factorization.

21110021231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85465705.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21110021231 its reverse (13212001112), we get a palindrome (34322022343).

The spelling of 21110021231 in words is "twenty-one billion, one hundred ten million, twenty-one thousand, two hundred thirty-one".