243420261 has 16 divisors (see below), whose sum is σ = 371472000. Its totient is φ = 138892608.

The previous prime is 243420227. The next prime is 243420283. The reversal of 243420261 is 162024342.

It is not a de Polignac number, because 243420261 - 2¹¹ = 243418213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243420211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6715 + ... + 23063.

It is an arithmetic number, because the mean of its divisors is an integer number (23217000).

Almost surely, 2^243420261 is an apocalyptic number.

243420261 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

243420261 is a deficient number, since it is larger than the sum of its proper divisors (128051739).

243420261 is a wasteful number, since it uses less digits than its factorization.

243420261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17068.

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 243420261 is about 15601.9313227562. The cubic root of 243420261 is about 624.3846838030.

The spelling of 243420261 in words is "two hundred forty-three million, four hundred twenty thousand, two hundred sixty-one".