243551133081 has 9 divisors (see below), whose sum is σ = 351798219669. Its totient is φ = 162366435036.

The previous prime is 243551133073. The next prime is 243551133101. The reversal of 243551133081 is 180331155342.

The square root of 243551133081 is 493509.

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

243551133081 is a `hidden beast` number, since 2 + 4 + 35 + 511 + 3 + 30 + 81 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 243551133081 - 2³ = 243551133073 is a prime.

It is a super-2 number, since 2×243551133081² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (243551133071) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1398276 + ... + 1562778.

Almost surely, 2^243551133081 is an apocalyptic number.

243551133081 is the 493509-th square number.

243551133081 is the 246755-th centered octagonal number.

It is an amenable number.

243551133081 is a deficient number, since it is larger than the sum of its proper divisors (108247086588).

243551133081 is an frugal number, since it uses more digits than its factorization.

243551133081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329012 (or 164506 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

Multiplying 243551133081 by its sum of digits (36), we get a square (8767840790916 = 2961054²).

The spelling of 243551133081 in words is "two hundred forty-three billion, five hundred fifty-one million, one hundred thirty-three thousand, eighty-one".