243874581 has 4 divisors (see below), whose sum is σ = 325166112. Its totient is φ = 162583052.

The previous prime is 243874567. The next prime is 243874583. The reversal of 243874581 is 185478342.

243874581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 243874581 - 2¹¹ = 243872533 is a prime.

It is a super-2 number, since 2×243874581² = 118949622515851122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243874583) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40645761 + ... + 40645766.

It is an arithmetic number, because the mean of its divisors is an integer number (81291528).

Almost surely, 2^243874581 is an apocalyptic number.

It is an amenable number.

243874581 is a deficient number, since it is larger than the sum of its proper divisors (81291531).

243874581 is an equidigital number, since it uses as much as digits as its factorization.

243874581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81291530.

The product of its digits is 215040, while the sum is 42.

The square root of 243874581 is about 15616.4842714357. The cubic root of 243874581 is about 624.7728932727.

The spelling of 243874581 in words is "two hundred forty-three million, eight hundred seventy-four thousand, five hundred eighty-one".