261079949 has 4 divisors (see below), whose sum is σ = 281163036. Its totient is φ = 240996864.

The previous prime is 261079943. The next prime is 261079991. The reversal of 261079949 is 949970162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 949970162 = 2 ⋅474985081.

It can be written as a sum of positive squares in 2 ways, for example, as 58216900 + 202863049 = 7630^2 + 14243^2 .

It is a cyclic number.

It is not a de Polignac number, because 261079949 - 2⁴ = 261079933 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 (261079943) 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, 10041524 + ... + 10041549.

It is an arithmetic number, because the mean of its divisors is an integer number (70290759).

Almost surely, 2^261079949 is an apocalyptic number.

It is an amenable number.

261079949 is a deficient number, since it is larger than the sum of its proper divisors (20083087).

261079949 is a wasteful number, since it uses less digits than its factorization.

261079949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20083086.

The product of its (nonzero) digits is 244944, while the sum is 47.

The square root of 261079949 is about 16157.9685913793. The cubic root of 261079949 is about 639.1328988218.

The spelling of 261079949 in words is "two hundred sixty-one million, seventy-nine thousand, nine hundred forty-nine".