231328021 has 8 divisors (see below), whose sum is σ = 246840320. Its totient is φ = 216149472.

The previous prime is 231328001. The next prime is 231328051. The reversal of 231328021 is 120823132.

231328021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 231328021 - 2¹⁷ = 231196949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 231327983 and 231328001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231328001) 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, 82005 + ... + 84778.

It is an arithmetic number, because the mean of its divisors is an integer number (30855040).

Almost surely, 2^231328021 is an apocalyptic number.

It is an amenable number.

231328021 is a deficient number, since it is larger than the sum of its proper divisors (15512299).

231328021 is a wasteful number, since it uses less digits than its factorization.

231328021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166875.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 231328021 is about 15209.4714240831. The cubic root of 231328021 is about 613.8695349989.

The spelling of 231328021 in words is "two hundred thirty-one million, three hundred twenty-eight thousand, twenty-one".