231756550921 has 27 divisors (see below), whose sum is σ = 272787079509. Its totient is φ = 196323257088.

The previous prime is 231756550919. The next prime is 231756550931. The reversal of 231756550921 is 129055657132.

The square root of 231756550921 is 481411.

It is a perfect power (a square), and thus also a powerful number.

231756550921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 46136892025 + 185619658896 = 214795^2 + 430836^2 .

It is not a de Polignac number, because 231756550921 - 2¹ = 231756550919 is a prime.

It is a super-2 number, since 2×231756550921² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (231756550931) 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 26 ways as a sum of consecutive naturals, for example, 326877715 + ... + 326878423.

It is an arithmetic number, because the mean of its divisors is an integer number (10103225167).

Almost surely, 2^231756550921 is an apocalyptic number.

231756550921 is the 481411-st square number.

231756550921 is the 240706-th centered octagonal number.

It is an amenable number.

231756550921 is a deficient number, since it is larger than the sum of its proper divisors (41030528588).

231756550921 is an frugal number, since it uses more digits than its factorization.

231756550921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1626 (or 813 counting only the distinct ones).

The product of its (nonzero) digits is 567000, while the sum is 46.

It can be divided in two parts, 23175 and 6550921, that added together give a square (6574096 = 2564²).

The spelling of 231756550921 in words is "two hundred thirty-one billion, seven hundred fifty-six million, five hundred fifty thousand, nine hundred twenty-one".