21100233231 has 48 divisors (see below), whose sum is σ = 38081691648. Its totient is φ = 10937217600.

The previous prime is 21100233227. The next prime is 21100233239. The reversal of 21100233231 is 13233200112.

It is not a de Polignac number, because 21100233231 - 2² = 21100233227 is a prime.

It is a super-2 number, since 2×21100233231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100233239) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 286450 + ... + 352496.

It is an arithmetic number, because the mean of its divisors is an integer number (793368576).

Almost surely, 2^21100233231 is an apocalyptic number.

21100233231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21100233231 is a deficient number, since it is larger than the sum of its proper divisors (16981458417).

21100233231 is a wasteful number, since it uses less digits than its factorization.

21100233231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66532 (or 66529 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21100233231 its reverse (13233200112), we get a palindrome (34333433343).

The spelling of 21100233231 in words is "twenty-one billion, one hundred million, two hundred thirty-three thousand, two hundred thirty-one".