261443379 has 4 divisors (see below), whose sum is σ = 348591176. Its totient is φ = 174295584.

The previous prime is 261443359. The next prime is 261443383. The reversal of 261443379 is 973344162.

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

It is not a de Polignac number, because 261443379 - 2⁷ = 261443251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261443359) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43573894 + ... + 43573899.

It is an arithmetic number, because the mean of its divisors is an integer number (87147794).

Almost surely, 2^261443379 is an apocalyptic number.

261443379 is a deficient number, since it is larger than the sum of its proper divisors (87147797).

261443379 is an equidigital number, since it uses as much as digits as its factorization.

261443379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87147796.

The product of its digits is 108864, while the sum is 39.

The square root of 261443379 is about 16169.2108341749. The cubic root of 261443379 is about 639.4293244616.

The spelling of 261443379 in words is "two hundred sixty-one million, four hundred forty-three thousand, three hundred seventy-nine".