21100223231 has 16 divisors (see below), whose sum is σ = 21893131008. Its totient is φ = 20320977600.

The previous prime is 21100223219. The next prime is 21100223233. The reversal of 21100223231 is 13232200112.

It is not a de Polignac number, because 21100223231 - 2⁶ = 21100223167 is a prime.

It is a super-2 number, since 2×21100223231² (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 (21100223233) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7100576 + ... + 7103546.

It is an arithmetic number, because the mean of its divisors is an integer number (1368320688).

Almost surely, 2^21100223231 is an apocalyptic number.

21100223231 is a deficient number, since it is larger than the sum of its proper divisors (792907777).

21100223231 is a wasteful number, since it uses less digits than its factorization.

21100223231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5182.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21100223231 its reverse (13232200112), we get a palindrome (34332423343).

The spelling of 21100223231 in words is "twenty-one billion, one hundred million, two hundred twenty-three thousand, two hundred thirty-one".