261031679 has 4 divisors (see below), whose sum is σ = 262115040. Its totient is φ = 259948320.

The previous prime is 261031657. The next prime is 261031691. The reversal of 261031679 is 976130162.

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 261031679 - 2⁸ = 261031423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261031699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 541319 + ... + 541800.

It is an arithmetic number, because the mean of its divisors is an integer number (65528760).

Almost surely, 2^261031679 is an apocalyptic number.

261031679 is a deficient number, since it is larger than the sum of its proper divisors (1083361).

261031679 is a wasteful number, since it uses less digits than its factorization.

261031679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1083360.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 261031679 is about 16156.4748320913. The cubic root of 261031679 is about 639.0935075081.

The spelling of 261031679 in words is "two hundred sixty-one million, thirty-one thousand, six hundred seventy-nine".