231232021 has 4 divisors (see below), whose sum is σ = 232524000. Its totient is φ = 229940044.

The previous prime is 231232009. The next prime is 231232061. The reversal of 231232021 is 120232132.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 231232021 - 2⁵ = 231231989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 231231986 and 231232004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231232061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 645721 + ... + 646078.

It is an arithmetic number, because the mean of its divisors is an integer number (58131000).

Almost surely, 2^231232021 is an apocalyptic number.

It is an amenable number.

231232021 is a deficient number, since it is larger than the sum of its proper divisors (1291979).

231232021 is a wasteful number, since it uses less digits than its factorization.

231232021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1291978.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 231232021 is about 15206.3151683766. The cubic root of 231232021 is about 613.7846056288.

Adding to 231232021 its reverse (120232132), we get a palindrome (351464153).

The spelling of 231232021 in words is "two hundred thirty-one million, two hundred thirty-two thousand, twenty-one".