231504550221 has 48 divisors (see below), whose sum is σ = 374820037760. Its totient is φ = 124461912960.

The previous prime is 231504550201. The next prime is 231504550237. The reversal of 231504550221 is 122055405132.

It is not a de Polignac number, because 231504550221 - 2¹⁰ = 231504549197 is a prime.

It is a super-2 number, since 2×231504550221² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231504550201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 506835 + ... + 848463.

Almost surely, 2^231504550221 is an apocalyptic number.

231504550221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

231504550221 is a deficient number, since it is larger than the sum of its proper divisors (143315487539).

231504550221 is a wasteful number, since it uses less digits than its factorization.

231504550221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341746 (or 341723 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 231504550221 its reverse (122055405132), we get a palindrome (353559955353).

The spelling of 231504550221 in words is "two hundred thirty-one billion, five hundred four million, five hundred fifty thousand, two hundred twenty-one".