231521061000 has 256 divisors, whose sum is σ = 763727328000. Its totient is φ = 58230835200.

The previous prime is 231521060989. The next prime is 231521061007. The reversal of 231521061000 is 160125132.

231521061000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (231521061007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13044132 + ... + 13061868.

It is an arithmetic number, because the mean of its divisors is an integer number (2983309875).

Almost surely, 2^231521061000 is an apocalyptic number.

231521061000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231521061000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (381863664000).

231521061000 is an abundant number, since it is smaller than the sum of its proper divisors (532206267000).

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

231521061000 is a wasteful number, since it uses less digits than its factorization.

231521061000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18009 (or 17995 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

Adding to 231521061000 its reverse (160125132), we get a palindrome (231681186132).

The spelling of 231521061000 in words is "two hundred thirty-one billion, five hundred twenty-one million, sixty-one thousand".