231221984 has 72 divisors (see below), whose sum is σ = 532617120. Its totient is φ = 98520576.

The previous prime is 231221983. The next prime is 231222011. The reversal of 231221984 is 489122132.

231221984 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a self number, because there is not a number n which added to its sum of digits gives 231221984.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231221983) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 374444 + ... + 375060.

It is an arithmetic number, because the mean of its divisors is an integer number (7397460).

Almost surely, 2^231221984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231221984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266308560).

231221984 is an abundant number, since it is smaller than the sum of its proper divisors (301395136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231221984 is a wasteful number, since it uses less digits than its factorization.

231221984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880 (or 865 counting only the distinct ones).

The product of its digits is 6912, while the sum is 32.

The square root of 231221984 is about 15205.9851374385. The cubic root of 231221984 is about 613.7757247290.

The spelling of 231221984 in words is "two hundred thirty-one million, two hundred twenty-one thousand, nine hundred eighty-four".