261339461 has 4 divisors (see below), whose sum is σ = 261475500. Its totient is φ = 261203424.

The previous prime is 261339451. The next prime is 261339493. The reversal of 261339461 is 164933162.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 164933162 = 2 ⋅82466581.

It can be written as a sum of positive squares in 2 ways, for example, as 219336100 + 42003361 = 14810^2 + 6481^2 .

It is a cyclic number.

It is not a de Polignac number, because 261339461 - 2¹⁴ = 261323077 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 (261339451) 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, 65096 + ... + 68993.

It is an arithmetic number, because the mean of its divisors is an integer number (65368875).

Almost surely, 2^261339461 is an apocalyptic number.

It is an amenable number.

261339461 is a deficient number, since it is larger than the sum of its proper divisors (136039).

261339461 is a wasteful number, since it uses less digits than its factorization.

261339461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136038.

The product of its digits is 23328, while the sum is 35.

The square root of 261339461 is about 16165.9970617342. The cubic root of 261339461 is about 639.3445935310.

The spelling of 261339461 in words is "two hundred sixty-one million, three hundred thirty-nine thousand, four hundred sixty-one".