261147541 has 4 divisors (see below), whose sum is σ = 263543500. Its totient is φ = 258751584.

The previous prime is 261147529. The next prime is 261147547. The reversal of 261147541 is 145741162.

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

It can be written as a sum of positive squares in 2 ways, for example, as 162562500 + 98585041 = 12750^2 + 9929^2 .

It is a cyclic number.

It is not a de Polignac number, because 261147541 - 2²⁷ = 126929813 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 (261147547) 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, 1197816 + ... + 1198033.

It is an arithmetic number, because the mean of its divisors is an integer number (65885875).

Almost surely, 2^261147541 is an apocalyptic number.

It is an amenable number.

261147541 is a deficient number, since it is larger than the sum of its proper divisors (2395959).

261147541 is a wasteful number, since it uses less digits than its factorization.

261147541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2395958.

The product of its digits is 6720, while the sum is 31.

The square root of 261147541 is about 16160.0600555815. The cubic root of 261147541 is about 639.1880499271.

The spelling of 261147541 in words is "two hundred sixty-one million, one hundred forty-seven thousand, five hundred forty-one".