231121233021 has 16 divisors (see below), whose sum is σ = 359678029824. Its totient is φ = 129259290864.

The previous prime is 231121233019. The next prime is 231121233041. The reversal of 231121233021 is 120332121132.

It is not a de Polignac number, because 231121233021 - 2¹ = 231121233019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231121233001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117081705 + ... + 117083678.

It is an arithmetic number, because the mean of its divisors is an integer number (22479876864).

Almost surely, 2^231121233021 is an apocalyptic number.

231121233021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

231121233021 is a deficient number, since it is larger than the sum of its proper divisors (128556796803).

231121233021 is a wasteful number, since it uses less digits than its factorization.

231121233021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234165440.

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

Adding to 231121233021 its reverse (120332121132), we get a palindrome (351453354153).

The spelling of 231121233021 in words is "two hundred thirty-one billion, one hundred twenty-one million, two hundred thirty-three thousand, twenty-one".