243965961 has 36 divisors (see below), whose sum is σ = 369784272. Its totient is φ = 154877184.

The previous prime is 243965957. The next prime is 243965971. The reversal of 243965961 is 169569342.

243965961 is a `hidden beast` number, since 24 + 39 + 6 + 596 + 1 = 666.

It is not a de Polignac number, because 243965961 - 2² = 243965957 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (243965971) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2515065 + ... + 2515161.

Almost surely, 2^243965961 is an apocalyptic number.

It is an amenable number.

243965961 is a deficient number, since it is larger than the sum of its proper divisors (125818311).

243965961 is an equidigital number, since it uses as much as digits as its factorization.

243965961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310 (or 210 counting only the distinct ones).

The product of its digits is 349920, while the sum is 45.

The square root of 243965961 is about 15619.4097519721. The cubic root of 243965961 is about 624.8509178287.

The spelling of 243965961 in words is "two hundred forty-three million, nine hundred sixty-five thousand, nine hundred sixty-one".