243961331 has 4 divisors (see below), whose sum is σ = 245055552. Its totient is φ = 242867112.

The previous prime is 243961327. The next prime is 243961337. The reversal of 243961331 is 133169342.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 243961331 - 2² = 243961327 is a prime.

It is a super-2 number, since 2×243961331² = 119034262046583122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243961337) 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, 546776 + ... + 547221.

It is an arithmetic number, because the mean of its divisors is an integer number (61263888).

Almost surely, 2^243961331 is an apocalyptic number.

243961331 is a deficient number, since it is larger than the sum of its proper divisors (1094221).

243961331 is a wasteful number, since it uses less digits than its factorization.

243961331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1094220.

The product of its digits is 11664, while the sum is 32.

The square root of 243961331 is about 15619.2615382418. The cubic root of 243961331 is about 624.8469649848.

The spelling of 243961331 in words is "two hundred forty-three million, nine hundred sixty-one thousand, three hundred thirty-one".