21231132231 has 8 divisors (see below), whose sum is σ = 28309777264. Its totient is φ = 14153287680.

The previous prime is 21231132173. The next prime is 21231132269. The reversal of 21231132231 is 13223113212.

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

It is not a de Polignac number, because 21231132231 - 2⁷ = 21231132103 is a prime.

It is a super-2 number, since 2×21231132231² (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 = 21231132198 and 21231132207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231132281) 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, 135226 + ... + 246471.

It is an arithmetic number, because the mean of its divisors is an integer number (3538722158).

Almost surely, 2^21231132231 is an apocalyptic number.

21231132231 is a deficient number, since it is larger than the sum of its proper divisors (7078645033).

21231132231 is a wasteful number, since it uses less digits than its factorization.

21231132231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400241.

The product of its digits is 432, while the sum is 21.

Adding to 21231132231 its reverse (13223113212), we get a palindrome (34454245443).

The spelling of 21231132231 in words is "twenty-one billion, two hundred thirty-one million, one hundred thirty-two thousand, two hundred thirty-one".