231221024420 has 24 divisors (see below), whose sum is σ = 485625235704. Its totient is φ = 92476774656.

The previous prime is 231221024407. The next prime is 231221024459. The reversal of 231221024420 is 24420122132.

It can be written as a sum of positive squares in 4 ways, for example, as 14581045504 + 216639978916 = 120752^2 + 465446^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 563339 + ... + 883058.

It is an arithmetic number, because the mean of its divisors is an integer number (20234384821).

Almost surely, 2^231221024420 is an apocalyptic number.

231221024420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231221024420 is an abundant number, since it is smaller than the sum of its proper divisors (254404211284).

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

231221024420 is a wasteful number, since it uses less digits than its factorization.

231221024420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1454399 (or 1454397 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 231221024420 its reverse (24420122132), we get a palindrome (255641146552).

The spelling of 231221024420 in words is "two hundred thirty-one billion, two hundred twenty-one million, twenty-four thousand, four hundred twenty".